environments: don't fail setup-local on a malformed databricks.yml

[rugpanov]

Problem

databricks environments setup-local loads the bundle on every invocation via the shared PreRunE (root.MustWorkspaceClient). A malformed databricks.yml — e.g. two targets both marked default — therefore surfaces a bundle-config error and aborts the command before it does any of its own work, even though the bundle is only ever consulted as an optional source of bundle.cluster_id.

$ databricks environments setup-local
Error: multiple targets are marked as default (dev, dev2)

This also blocked explicit compute flags (--serverless-version 5 --dry-run failed the same way); only --target dev, which resolves the ambiguity, worked.

Root cause

The bundle load runs the SelectDefaultTarget mutator, which errors on two default targets. The error is logged via logdiag on the shared command context during PreRunE, and MustWorkspaceClient returns ErrAlreadyPrinted — killing the command before runPipeline.

Fix

• PreRunE wraps MustWorkspaceClient with root.SkipLoadBundle (the same pattern cmd/sync uses), so a broken bundle can't fail auth setup up front. Auth still resolves from profile/env.

• bundleTarget (the cluster_id fallback) loads the bundle in an isolated, buffered logdiag context. Any load error is debug-logged and treated as "no bundle target", so the pipeline falls through to its existing E_NO_TARGET:

  resolve  error  No compute target is selected. Select a cluster or serverless target,
                  or pass --cluster-id / --cluster-name / --serverless-version / --job-task
  

Valid bundles with a cluster_id still resolve as before.

Tests

• Adds acceptance test acceptance/localenv/bundle-multiple-defaults (two-default databricks.yml → reaches E_NO_TARGET, no bundle-error leak).
• Verified manually: broken bundle → E_NO_TARGET; --serverless-version 5 --dry-run → works; --debug preserves the bundle error as a debug line; valid cluster_id fallback still resolves.

Found during the M5 bug bash (DECO-27936).

This pull request and its description were written by Isaac.

[github-actions]

Approval status: pending

/acceptance/localenv/ - needs approval

5 files changed
Eligible: @rclarey, @anton-107, @misha-db

/cmd/environments/ - needs approval

Files: cmd/environments/sync.go
Eligible: @rclarey, @anton-107, @misha-db

_{Any maintainer (@andrewnester, @anton-107, @denik, @pietern, @shreyas-goenka, @simonfaltum, @renaudhartert-db, @janniklasrose, @lennartkats-db) can approve all areas.
See OWNERS for ownership rules.}

[eng-dev-ecosystem-bot]

Integration test report

Commit: 4b11a08

Run: 31197020379

	Env	❌​FAIL	🟨​KNOWN	💚​RECOVERED	🙈​SKIP	✅​pass	🙈​skip	Time
❌​	aws linux	1	1	3	4	292	1116	4:54
❌​	aws windows	1	1	3	4	294	1114	5:16
❌​	azure linux	1	1	3	4	291	1116	5:39
❌​	azure windows	1	1	3	4	293	1114	8:11
❌​	gcp linux	1	1		5	292	1116	4:59
❌​	gcp windows	1	1		5	294	1114	6:08

9 interesting tests: 4 SKIP, 3 RECOVERED, 1 KNOWN, 1 FAIL

	Test Name	aws linux	aws windows	azure linux	azure windows	gcp linux	gcp windows
🟨​	TestAccept	🟨​K	🟨​K	🟨​K	🟨​K	🟨​K	🟨​K
🙈​	TestAccept/bundle/invariant/no_drift	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
❌​	TestAccept/bundle/resources/model_serving_endpoints/drift/recreated_same_name	❌​F	❌​F	❌​F	❌​F	❌​F	❌​F
🙈​	TestAccept/bundle/resources/vector_search_endpoints/drift/recreated_same_name	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
🙈​	TestAccept/bundle/resources/vector_search_indexes/recreate/embedding_dimension	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
🙈​	TestAccept/ssh/connection	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S	🙈​S
💚​	TestFetchRepositoryInfoAPI_FromRepo	💚​R	💚​R	💚​R	💚​R	🙈​S	🙈​S
💚​	TestFetchRepositoryInfoAPI_FromRepo/root	💚​R	💚​R	💚​R	💚​R
💚​	TestFetchRepositoryInfoAPI_FromRepo/subdir	💚​R	💚​R	💚​R	💚​R