refactor(runway): collapse orchestrator into single-service domain (#272)

## Summary

### Why?

Runway only ever had a single service, so the per-domain `gateway/` +
`orchestrator/` split wrapped it in an empty service layer. Making the
runway domain *be* the service removes that indirection and matches how
runway actually works — a consumer-only landing service with no gateway.

### What?

Collapses the `orchestrator` service segment out of the runway domain:

- `runway/orchestrator/controller/*` → `runway/controller/*`
- `api/runway/orchestrator/{proto,protopb}` →
`api/runway/{proto,protopb}`
- `example/runway/orchestrator/{client,server}` →
`example/runway/{client,server}`

The proto package becomes `uber.runway` (was `uber.runway.orchestrator`)
and the RPC service `RunwayOrchestrator` becomes `Runway`. Server/client
identifiers, metric scope, and the `ServiceName` ping field follow suit.
Build tooling (`tool/proto`, `Makefile` targets, `docker-compose.yml`,
`Dockerfile`) and docs (`CLAUDE.md`, `runway/README.md`, runway workflow
RFC) are updated, documenting the single-service-domain pattern.

## Test Plan

- ✅ `make build`
- ✅ `make proto` + `make gazelle` (idempotent)
- ✅ runway tests: `//runway/...`, `//api/runway/...`,
`//example/runway/...`

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: behinddwalls

BUILD.bazel

@@ -10,7 +10,7 @@ load("@gazelle//:def.bzl", "gazelle")
 # gazelle:resolve go github.com/uber/submitqueue/api/base/change/protopb //api/base/change/protopb
 # gazelle:resolve go github.com/uber/submitqueue/api/base/mergestrategy/protopb //api/base/mergestrategy/protopb
 # gazelle:resolve go github.com/uber/submitqueue/api/runway/messagequeue/protopb //api/runway/messagequeue/protopb
-# gazelle:resolve go github.com/uber/submitqueue/api/runway/orchestrator/protopb //api/runway/orchestrator/protopb
+# gazelle:resolve go github.com/uber/submitqueue/api/runway/protopb //api/runway/protopb
 # gazelle:resolve go github.com/uber/submitqueue/api/submitqueue/gateway/protopb //api/submitqueue/gateway/protopb
 # gazelle:resolve go github.com/uber/submitqueue/api/submitqueue/orchestrator/protopb //api/submitqueue/orchestrator/protopb
 # gazelle:resolve go github.com/uber/submitqueue/api/stovepipe/protopb //api/stovepipe/protopb

CLAUDE.md

@@ -39,6 +39,7 @@ submitqueue/                        # repo root (Go module github.com/uber/submi
 ├── api/                            # Published wire contracts (cross-domain/external)
 │   ├── submitqueue/{gateway,orchestrator}/{proto,protopb}/   # RPC (proto)
 │   ├── stovepipe/{proto,protopb}/  # single-service RPC (proto) — no service segment yet
+│   ├── runway/{proto,protopb}/     # RPC (proto) — single-service domain, no service segment
 │   └── runway/messagequeue/        # external queue contracts (proto + protojson)
 ├── platform/                       # SHARED cross-domain packages — no domain deps
 │   ├── errs/, metrics/, consumer/, http/
@@ -52,20 +53,23 @@ submitqueue/                        # repo root (Go module github.com/uber/submi
 │   └── core/                       # SubmitQueue-internal shared infra (consumer wiring, request, topickey, …)
 ├── stovepipe/                      # Stovepipe domain (single Ping-only service for now)
 │   └── controller/                 # Business logic (currently just Ping); entity/extension/core added as it grows
+├── runway/                         # Runway domain (single service — the domain *is* the service)
+│   └── controller/                 # Runway service controllers (consumes the merge queues; no gateway/orchestrator split)
 ├── tool/                           # Development and CI tooling
 ├── example/
 │   ├── submitqueue/                # Runnable SubmitQueue servers/clients + Docker Compose
-│   └── stovepipe/                  # Runnable Stovepipe servers/clients
+│   ├── stovepipe/                  # Runnable Stovepipe servers/clients
+│   └── runway/                     # Runnable Runway server/client + Docker Compose
 ├── test/
 │   ├── e2e/submitqueue/            # End-to-end tests (full stack)
 │   ├── integration/                # Integration tests (platform/, submitqueue/, stovepipe/, …)
 │   └── testutil/                   # Test utilities (ComposeStack, MySQL helpers)
 └── doc/                            # Documentation
 ```
 
-The `platform/` tree holds code reused across domains (infrastructure, shared entities, shared extension contracts). Each **domain** (`submitqueue/`, `stovepipe/`, …) grows into the same internal layout (`gateway/`, `orchestrator/`, `entity/`, `extension/`, `core/`); a domain's own `core/` (e.g. `submitqueue/core/`) holds infra shared only between that domain's services. A domain may start smaller — Stovepipe is currently a single Ping-only service with just `controller/` (and a service-segment-free `api/stovepipe/`), adding the other layers as it gains real behavior.
+The `platform/` tree holds code reused across domains (infrastructure, shared entities, shared extension contracts). A multi-service **domain** (e.g. `submitqueue/`) keeps the same internal layout (`gateway/`, `orchestrator/`, `entity/`, `extension/`, `core/`); a domain's own `core/` (e.g. `submitqueue/core/`) holds infra shared only between that domain's services. A **single-service domain** collapses that split — the domain *is* the service, so its controllers live directly under the domain root (e.g. `runway/controller/`, `stovepipe/controller/`) with no `gateway/`/`orchestrator/` segment, and its wire contract is service-segment-free (`api/{domain}/`). `runway` is a consumer-only landing service with no gateway; `stovepipe` is currently a single Ping-only service that can grow the other layers (`entity/`, `extension/`, `core/`) as it gains real behavior.
 
-The `api/` tree holds **published** wire contracts — those depended on from outside the owning domain. RPC contracts live at `api/{domain}/{service}/` (`proto/` for `.proto` sources, `protopb/` for committed generated Go); a service package may hold multiple `.proto` files, all generating into the same `protopb/`. External message-queue contracts live at `api/{domain}/messagequeue/` (see Message Queue Contracts below). Internal queue contracts do **not** go here — they live under `{domain}/core/messagequeue/`.
+The `api/` tree holds **published** wire contracts — those depended on from outside the owning domain. RPC contracts live at `api/{domain}/{service}/` (`proto/` for `.proto` sources, `protopb/` for committed generated Go); for a single-service domain the service segment is dropped, so the contract lives directly at `api/{domain}/` (e.g. `api/runway/{proto,protopb}/`). A service package may hold multiple `.proto` files, all generating into the same `protopb/`. External message-queue contracts live at `api/{domain}/messagequeue/` (see Message Queue Contracts below). Internal queue contracts do **not** go here — they live under `{domain}/core/messagequeue/`.
 
 ### Platform notes
 
@@ -86,7 +90,7 @@ Each service follows the same layout:
         └── {step}_test.go
 ```
 
-Wire contracts for a service live separately under `api/{domain}/{service}/` (see Project Layout): `proto/` holds `.proto` sources and `protopb/` holds the committed generated stubs.
+Wire contracts for a service live separately under `api/{domain}/{service}/` (see Project Layout): `proto/` holds `.proto` sources and `protopb/` holds the committed generated stubs. For a single-service domain the service root *is* the domain root (e.g. `runway/controller/`), and its wire contract lives at `api/{domain}/` (e.g. `api/runway/`) with no service segment.
 
 ### Controllers
 
@@ -152,9 +156,9 @@ When in doubt, ask: *"If the next implementation were DynamoDB / Kafka / Bigtabl
 
 Paths follow the directory layout: shared packages live under `platform/` at the repo root; domain code nests under `submitqueue/`, `stovepipe/`, and other domain folders.
 
-- RPC Controllers: `github.com/uber/submitqueue/{domain}/{service}/controller` (e.g. `.../submitqueue/gateway/controller`)
-- Queue Controllers: `github.com/uber/submitqueue/{domain}/{service}/controller/{step}`
-- Proto (generated): `github.com/uber/submitqueue/api/{domain}/{service}/protopb`
+- RPC Controllers: `github.com/uber/submitqueue/{domain}/{service}/controller` (e.g. `.../submitqueue/gateway/controller`; single-service domains drop the `{service}` segment, e.g. `.../runway/controller`)
+- Queue Controllers: `github.com/uber/submitqueue/{domain}/{service}/controller/{step}` (single-service: `.../runway/controller/{step}`, e.g. `.../runway/controller/merge`)
+- Proto (generated): `github.com/uber/submitqueue/api/{domain}/{service}/protopb` (single-service: `.../api/{domain}/protopb`, e.g. `.../api/runway/protopb`)
 - Queue contracts: external `github.com/uber/submitqueue/api/{domain}/messagequeue`; internal `github.com/uber/submitqueue/{domain}/core/messagequeue`
 - Domain entities: `github.com/uber/submitqueue/{domain}/entity` (e.g. `.../submitqueue/entity`)
 - Domain extensions: `github.com/uber/submitqueue/{domain}/extension/{ext}[/{impl}]` (e.g. `.../submitqueue/extension/storage/mysql`)

Makefile

@@ -19,7 +19,7 @@ STOVEPIPE_COMPOSE_FILE = example/stovepipe/docker-compose.yml
 STOVEPIPE_LOCAL_PROJECT = stovepipe
 
 # Runway compose files
-RUNWAY_ORCHESTRATOR_COMPOSE_FILE = example/runway/orchestrator/server/docker-compose.yml
+RUNWAY_COMPOSE_FILE = example/runway/server/docker-compose.yml
 
 # Fixed project name for local manual testing (tests use unique random names)
 RUNWAY_LOCAL_PROJECT = runway
@@ -35,7 +35,7 @@ GOIMPORTS_VERSION ?= v0.33.0
 # (the out_dir convention in tool/proto/BUILD.bazel) and copied back here. A
 # package may hold multiple .proto files (e.g. an RPC contract plus messagequeue
 # contracts); all generated stubs land in the same protopb/ dir.
-PROTO_PACKAGES = api/base/change api/base/mergestrategy api/base/messagequeue api/runway/messagequeue api/runway/orchestrator api/submitqueue/gateway api/submitqueue/orchestrator api/stovepipe
+PROTO_PACKAGES = api/base/change api/base/mergestrategy api/base/messagequeue api/runway/messagequeue api/runway api/submitqueue/gateway api/submitqueue/orchestrator api/stovepipe
 
 # Set REPO_ROOT for docker-compose
 export REPO_ROOT := $(shell pwd)
@@ -51,7 +51,7 @@ define assert_clean
 	fi
 endef
 
-.PHONY: build build-all-linux build-runway-orchestrator-linux build-submitqueue-gateway-linux build-submitqueue-orchestrator-linux build-stovepipe-linux check-gazelle check-mocks check-tidy clean clean-proto deps e2e-test fmt gazelle integration-test integration-test-submitqueue-consumer integration-test-extensions integration-test-submitqueue-gateway integration-test-submitqueue-orchestrator license-fix lint lint-fmt lint-license local-init-runway-queue-schema local-runway-orchestrator-start local-runway-orchestrator-stop local-submitqueue-clean local-submitqueue-gateway-start local-submitqueue-gateway-stop local-init-submitqueue-schemas local-submitqueue-logs local-submitqueue-orchestrator-start local-submitqueue-orchestrator-stop local-submitqueue-ps local-submitqueue-restart local-submitqueue-start local-stop local-stovepipe-logs local-stovepipe-start local-stovepipe-stop mocks proto query-deps query-targets run-client-runway-orchestrator run-client-submitqueue-gateway run-client-submitqueue-orchestrator run-client-stovepipe run-queue-admin test test-no-cache tidy tidy-bazel tidy-go help
+.PHONY: build build-all-linux build-runway-linux build-submitqueue-gateway-linux build-submitqueue-orchestrator-linux build-stovepipe-linux check-gazelle check-mocks check-tidy clean clean-proto deps e2e-test fmt gazelle integration-test integration-test-submitqueue-consumer integration-test-extensions integration-test-submitqueue-gateway integration-test-submitqueue-orchestrator license-fix lint lint-fmt lint-license local-init-runway-queue-schema local-runway-start local-runway-stop local-submitqueue-clean local-submitqueue-gateway-start local-submitqueue-gateway-stop local-init-submitqueue-schemas local-submitqueue-logs local-submitqueue-orchestrator-start local-submitqueue-orchestrator-stop local-submitqueue-ps local-submitqueue-restart local-submitqueue-start local-stop local-stovepipe-logs local-stovepipe-start local-stovepipe-stop mocks proto query-deps query-targets run-client-runway run-client-submitqueue-gateway run-client-submitqueue-orchestrator run-client-stovepipe run-queue-admin test test-no-cache tidy tidy-bazel tidy-go help
 
 
 build: ## Build all services and examples
@@ -60,16 +60,16 @@ build: ## Build all services and examples
 	@echo "Build complete!"
 
 # Build Linux binaries required for Docker containers
-build-all-linux: build-submitqueue-gateway-linux build-submitqueue-orchestrator-linux build-stovepipe-linux build-runway-orchestrator-linux ## Build all Linux binaries for Docker
+build-all-linux: build-submitqueue-gateway-linux build-submitqueue-orchestrator-linux build-stovepipe-linux build-runway-linux ## Build all Linux binaries for Docker
 	@echo "All Linux binaries ready for Docker"
 
-build-runway-orchestrator-linux: ## Build Runway orchestrator Linux binary for Docker
-	@echo "Building Runway orchestrator Linux binary for Docker..."
-	@$(BAZEL) build --platforms=@rules_go//go/toolchain:linux_amd64 //example/runway/orchestrator/server:orchestrator
+build-runway-linux: ## Build Runway Linux binary for Docker
+	@echo "Building Runway Linux binary for Docker..."
+	@$(BAZEL) build --platforms=@rules_go//go/toolchain:linux_amd64 //example/runway/server:runway
 	@mkdir -p .docker-bin
-	@cp -f bazel-bin/example/runway/orchestrator/server/orchestrator_/orchestrator .docker-bin/runway-orchestrator 2>/dev/null || \
-	 cp -f bazel-bin/example/runway/orchestrator/server/orchestrator .docker-bin/runway-orchestrator
-	@echo "Runway orchestrator Linux binary ready at .docker-bin/runway-orchestrator"
+	@cp -f bazel-bin/example/runway/server/runway_/runway .docker-bin/runway 2>/dev/null || \
+	 cp -f bazel-bin/example/runway/server/runway .docker-bin/runway
+	@echo "Runway Linux binary ready at .docker-bin/runway"
 
 build-submitqueue-gateway-linux: ## Build Gateway Linux binary for Docker
 	@echo "Building Gateway Linux binary for Docker..."
@@ -221,23 +221,23 @@ local-init-runway-queue-schema: ## Apply queue schema only (mysql-queue) for Run
 	done
 	@echo "✅ Runway queue schema applied successfully"
 
-local-runway-orchestrator-start: build-runway-orchestrator-linux ## Start Runway orchestrator locally (orchestrator + MySQL queue)
-	@echo "Starting Runway orchestrator with compose..."
-	@$(COMPOSE) -f $(RUNWAY_ORCHESTRATOR_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) up -d --build --wait
+local-runway-start: build-runway-linux ## Start Runway locally (runway + MySQL queue)
+	@echo "Starting Runway with compose..."
+	@$(COMPOSE) -f $(RUNWAY_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) up -d --build --wait
 	@echo "Applying queue schema to mysql-queue (no Runway app schema)..."
 	@$(MAKE) -s local-init-runway-queue-schema
 	@echo ""
-	@echo "✅ Runway orchestrator is running!"
+	@echo "✅ Runway is running!"
 	@echo ""
-	@$(COMPOSE) -f $(RUNWAY_ORCHESTRATOR_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) ps
+	@$(COMPOSE) -f $(RUNWAY_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) ps
 	@echo ""
-	@echo "Runway orchestrator gRPC port: $$(docker port $(RUNWAY_LOCAL_PROJECT)-orchestrator-service-1 8080 2>/dev/null | cut -d: -f2 || echo 'unknown')"
-	@echo "MySQL Queue port:              $$(docker port $(RUNWAY_LOCAL_PROJECT)-mysql-queue-1 3306 2>/dev/null | cut -d: -f2 || echo 'unknown')"
+	@echo "Runway gRPC port: $$(docker port $(RUNWAY_LOCAL_PROJECT)-runway-service-1 8080 2>/dev/null | cut -d: -f2 || echo 'unknown')"
+	@echo "MySQL Queue port: $$(docker port $(RUNWAY_LOCAL_PROJECT)-mysql-queue-1 3306 2>/dev/null | cut -d: -f2 || echo 'unknown')"
 
-local-runway-orchestrator-stop: ## Stop Runway orchestrator service
-	@echo "Stopping Runway orchestrator services..."
-	@$(COMPOSE) -f $(RUNWAY_ORCHESTRATOR_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) down
-	@echo "Runway orchestrator services stopped."
+local-runway-stop: ## Stop Runway service
+	@echo "Stopping Runway services..."
+	@$(COMPOSE) -f $(RUNWAY_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) down
+	@echo "Runway services stopped."
 
 local-submitqueue-logs: ## View logs from all running services
 	@$(COMPOSE) -f $(COMPOSE_FILE) -p $(SUBMITQUEUE_LOCAL_PROJECT) logs -f
@@ -304,7 +304,7 @@ local-stop: ## Stop all services (keep data)
 	@echo "Stopping all services..."
 	@$(COMPOSE) -f $(COMPOSE_FILE) -p $(SUBMITQUEUE_LOCAL_PROJECT) down
 	@$(COMPOSE) -f $(STOVEPIPE_COMPOSE_FILE) -p $(STOVEPIPE_LOCAL_PROJECT) down
-	@$(COMPOSE) -f $(RUNWAY_ORCHESTRATOR_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) down
+	@$(COMPOSE) -f $(RUNWAY_COMPOSE_FILE) -p $(RUNWAY_LOCAL_PROJECT) down
 	@echo "Services stopped. Data volumes preserved."
 
 local-stovepipe-logs: ## View logs from the running Stovepipe service
@@ -363,9 +363,9 @@ run-client-submitqueue-orchestrator:
 run-client-stovepipe:
 	@$(BAZEL) run //example/stovepipe/client:stovepipe -- -addr $(or $(SERVER_ADDR),localhost:8083) -message "$(or $(MESSAGE),ping)"
 
-# Run runway orchestrator client (connects to any running runway orchestrator service)
-run-client-runway-orchestrator:
-	@$(BAZEL) run //example/runway/orchestrator/client:orchestrator -- -addr $(or $(SERVER_ADDR),localhost:8086) -message "$(or $(MESSAGE),ping)"
+# Run runway client (connects to any running runway service)
+run-client-runway:
+	@$(BAZEL) run //example/runway/client:runway -- -addr $(or $(SERVER_ADDR),localhost:8086) -message "$(or $(MESSAGE),ping)"
 
 run-queue-admin: ## Run queue-admin CLI (use ARGS to pass arguments, e.g. make run-queue-admin ARGS="list-topics")
 	@$(BAZEL) run //platform/extension/messagequeue/mysql/ctl -- $(ARGS)