Merge origin/main (v1.64.1.0 code-smell wave) into test-evals-ci-speedup

Both sides shipped overlapping test-infra work in parallel; resolutions
compose intent rather than picking sides:

- free-tests.yml (both added): keep this branch's lane (canonical
  strict-parallel runner, secretless, plain runner, ~2min) over main's
  per-file-serial container loop (45min budget, hand-curated skip list,
  needs GITHUB_TOKEN); ported main's git safe.directory insight.
- Dockerfile.ci Bun install: main discovered the installer IGNORES the
  BUN_VERSION env var (the old form silently installed latest) — main's
  arg-form mechanism + this branch's 1.3.13 target.
- parity baseline: both sides rebased after hitting the same silent
  drift; adopted main's v1.64.1.0 union-normalized fixture and dropped
  this branch's interim v1.64.0.0 capture. carve-guards caps: main's
  tighter re-ratchets win (all four).
- touchfiles: kept this branch's three-file facade split; ported main's
  pure-data removals (dead sidebar-agent entries, spec judge entry,
  ship-idempotency) into touchfiles-data.ts.
- ship-idempotency SDK variant: main deliberately removed it as
  redundant with the real-PTY test; adopted — dropped this branch's
  rehomed copy and its periodic matrix row (the zombie-monolith deletion
  stands; coverage-audit + triage rehomes verified untouched by main).
- e2e-tier-alignment: taught the new parent-mapper hard check main's
  consolidated describeE2ETier()/e2eTierEnabled() self-gate shapes (the
  helper's header names this file as a required recognizer).
- browse/test/compare-board.test.ts: quarantined behind
  GSTACK_COMPARE_BOARD_TESTS=1 — all 16 tests fail identically on
  origin/main solo on dev machines (blame protocol receipts in-file);
  main's own CI lane skip-lists it. An always-red file would block every
  PR now that free-tests is a required check.

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

test/helpers/touchfiles-data.ts

@@ -284,7 +284,6 @@ export const E2E_TOUCHFILES: Record<string, string[]> = {
   // Plan completion audit + verification
   'ship-plan-completion': ['ship/**', 'scripts/gen-skill-docs.ts'],
   'ship-plan-verification': ['ship/**', 'qa-only/**', 'scripts/gen-skill-docs.ts'],
-  'ship-idempotency':       ['ship/**', 'scripts/resolvers/utility.ts'],
   'review-plan-completion': ['review/**', 'scripts/gen-skill-docs.ts'],
 
   // Design
@@ -316,10 +315,6 @@ export const E2E_TOUCHFILES: Record<string, string[]> = {
   'benchmark-workflow':            ['benchmark/**', 'browse/src/**'],
   'setup-deploy-workflow':         ['setup-deploy/**', 'scripts/gen-skill-docs.ts'],
 
-  // Sidebar agent
-  'sidebar-navigate':              ['browse/src/server.ts', 'browse/src/sidebar-agent.ts', 'browse/src/sidebar-utils.ts', 'extension/**'],
-  'sidebar-url-accuracy':          ['browse/src/server.ts', 'browse/src/sidebar-agent.ts', 'browse/src/sidebar-utils.ts', 'extension/background.js'],
-  'sidebar-css-interaction':       ['browse/src/server.ts', 'browse/src/sidebar-agent.ts', 'browse/src/write-commands.ts', 'browse/src/read-commands.ts', 'browse/src/cdp-inspector.ts', 'extension/**'],
 
   // Autoplan
   'autoplan-core':  ['autoplan/**', 'plan-ceo-review/**', 'plan-eng-review/**', 'plan-design-review/**'],
@@ -648,7 +643,6 @@ export const E2E_TIERS: Record<string, 'gate' | 'periodic'> = {
   'ship-triage': 'gate',
   'ship-plan-completion': 'gate',
   'ship-plan-verification': 'gate',
-  'ship-idempotency': 'periodic',
 
   // Retro — gate for cheap branch detection, periodic for full Opus retro
   'retro': 'periodic',
@@ -702,10 +696,6 @@ export const E2E_TIERS: Record<string, 'gate' | 'periodic'> = {
   'benchmark-workflow': 'gate',
   'setup-deploy-workflow': 'gate',
 
-  // Sidebar agent
-  'sidebar-navigate': 'periodic',
-  'sidebar-url-accuracy': 'periodic',
-  'sidebar-css-interaction': 'periodic',
 
   // Autoplan — periodic (not yet implemented)
   'autoplan-core': 'periodic',
@@ -776,7 +766,6 @@ export const LLM_JUDGE_TOUCHFILES: Record<string, string[]> = {
   'plan-eng-review/SKILL.md sections':    ['plan-eng-review/SKILL.md', 'plan-eng-review/SKILL.md.tmpl'],
 
   // /spec authored-spec quality (paid LLM-judge — periodic-tier).
-  'spec authored quality':                ['spec/SKILL.md', 'spec/SKILL.md.tmpl', 'test/fixtures/spec/**'],
   'plan-design-review/SKILL.md passes':   ['plan-design-review/SKILL.md', 'plan-design-review/SKILL.md.tmpl'],
 
   // Design skills