sync(bfmono): feat(gambit): simplify Codex login flow and auto-configure sandbox (+19 more) (bfmono@cd5bb33a9)

This PR is an automated gambitmono sync of bfmono Gambit packages.

- Source: `packages/gambit/`
- Core: `packages/gambit/packages/gambit-core/`
- bfmono rev: cd5bb33a9

Changes:
- cd5bb33a9 feat(gambit): simplify Codex login flow and auto-configure sandbox
- eee085e1c fix(gambit): handle non-file import.meta.url in jsr runtime paths
- fe98813a6 fix(gambit): replace dynamic import.meta.resolve at runtime
- 68953d21c chore(gambit): release 0.8.5
- 175e49006 fix(gambit-core): support non-file import.meta.url at runtime init
- 3c44ef51a fix(gambit): include core snippets/decks/workers in compile assets
- 591734506 fix(gambit): exclude .codex from Build file listing
- 4fe56b200 chore(gambit): cut 0.8.5-rc.12
- 2bfffaaae fix(gambit): add codex trust preflight for workbench chat
- 9c16505d6 chore(gambit): cut 0.8.5-rc.11
- b4d5cdaef fix(simulator-ui): prevent feedback reason text from being clobbered
- 84952a652 fix(gambit-verify): align verify turn labels and stabilize initial run filtering
- c56b7f52f feat(gambit): improve verify report controls and harden concurrent calibrate persistence
- beb9435c0 feat(gambit-simulator-ui): extend listbox trigger and popover options
- 25f9fdcfc fix(gambit-simulator-ui): align verify outlier chip semantics and display
- a010b0ee1 feat(gambit-simulator-ui): add verify outliers to workbench chat chips
- 383f2500a refactor(simulator-ui): replace nested ternaries in main routing
- 13c4c8c22 fix(gambit): preserve shared references in safe session serialization
- ae392aa24 feat(gambit-simulator-ui): add grader error chips to workbench chat
- 1de6b335c fix(gambit): clamp deck-level maxTurns bounds in test run selection

Do not edit this repo directly; make changes in bfmono and re-run the sync.

Author: bft-codebot

.env.example

@@ -0,0 +1,8 @@
+# Copy to .env (or .env.secrets if using direnv) for local development.
+
+# Optional: set this to use a non-default Codex config location.
+# By default, Codex uses the system user config (for example ~/.codex).
+# CODEX_HOME=~/.codex
+
+# Optional: custom Codex CLI binary path.
+# GAMBIT_CODEX_BIN=codex

README.md

@@ -78,6 +78,18 @@ open http://localhost:8000/debug
 
 Use the CLI to run decks locally, stream output, and capture traces/state.
 
+### Environment setup
+
+For local development, copy `.env.example` to `.env` if you want local
+overrides:
+
+```bash
+cp .env.example .env
+```
+
+Gambit uses your system Codex login/config by default. If you need a custom
+location, set `CODEX_HOME` explicitly.
+
 Run with npx (no install):
 
 ```