Merge origin/main (v1.65.0.0 fork port wave 2) into test-evals-ci-speedup

Second overlapping-wave merge; resolutions compose intent:

- TEST_ROOTS: ours is the superset (main also wired ios-qa/daemon/test;
  ours additionally has ios-qa/scripts + browser-skills). package.json
  'test' keeps routing through the canonical strict runner.
- gbrainAvailable: main fixed the same load-flake with a strictly better
  mechanism (memoized stat-based PATH scan, no subprocess at all) —
  theirs supersedes this branch's memoized-exec probe. Main also made
  the query timeout env-overridable (GSTACK_BRAIN_TIMEOUT_MS).
- Model defaults: adopted main's lib/eval-model.ts abstraction (one
  resolution point, env-overridable per kind) and applied decision D1a
  inside it: capture defaults to Sonnet (Opus opt-in via explicit arg or
  GSTACK_EVAL_MODEL_CAPTURE); test pins updated to follow.
- Parent watchdog: main's rewrite (named parameterized tick, driven
  deterministically by its test via __testInternals__, plus handoff
  suppression semantics from session persistence) supersedes this
  branch's env-tunable interval; adopted their server + test wholesale.
- windows-free-tests: ours (curated bun run test:windows) — main's
  hand-list grew by one more file, which the curated runner subsumes
  automatically; that drift is the reason for D11.
- context-skills 0-for-26 fix: both waves made the IDENTICAL fix; kept
  this branch's comment (carries the receipts).
- .gitignore: main's superset (also ignores Package.resolved — their
  never-commit call; untracked the copy this branch had committed).

Verified: 239-test merge battery green, watchdog 8/8, eval-model 5/5,
actionlint clean, eval:select works.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CLAUDE.md

@@ -165,11 +165,11 @@ gstack/
 │   ├── test/        # Integration tests
 │   └── dist/        # Compiled binary
 ├── extension/       # Chrome extension (side panel + activity feed + CSS inspector)
-├── lib/             # Shared libraries (worktree.ts, egress-receipt.ts, context-bill.ts, redact-engine.ts)
+├── lib/             # Shared libraries (worktree.ts, egress-receipt.ts, context-bill.ts, redact-engine.ts, code-intelligence/)
 ├── docs/designs/    # Design documents
 ├── setup-deploy/    # /setup-deploy skill (one-time deploy config)
 ├── .github/         # CI workflows + Docker image
-│   ├── workflows/   # evals.yml (E2E on Ubicloud), skill-docs.yml, actionlint.yml
+│   ├── workflows/   # evals.yml (E2E on Ubicloud), quality-gate.yml (secret scan), dependency-review.yml, osv-scanner.yml, skill-docs.yml, actionlint.yml, and 7 more (windows, periodic evals, release gates, ci-image)
 │   └── docker/      # Dockerfile.ci (pre-baked toolchain + Playwright/Chromium)
 ├── contrib/         # Contributor-only tools (never installed for users)
 │   └── add-host/    # /gstack-contrib-add-host skill