enhance(#3545): widen no-source-grep with fold+hooks, migrate 76 sites (#4161)

* feat(#3545): widen no-source-grep with one-hop path-fold and hooks dir

Resolve a readFileSync() path argument that is a bare Identifier one hop
back to its VariableDeclarator initializer before classification, and
recognize `hooks` as a source directory alongside bin/lib/gsd-core/src.

Measured (epic #3464 phase 7): fold+hooks together newly flag 76
unsuppressed sites across 18 files that were previously invisible to
identifier-indirected or hooks/-rooted source reads. Neither widening
alone is sufficient — hooks-only surfaces 0 new sites, confirming #3520's
prior finding that the identifier-indirection gap must close first.

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

* test(#3545): migrate 76 sites newly flagged by the fold+hooks widening

Per-site classification: rewrite behaviorally (require() the real module,
assert on its actual exported behavior) wherever the read was a proxy for
code behavior; add a site-scoped `// allow-test-rule: <reason> (#3545)`
marker only where the raw source text genuinely is the product under test
(codex-config.test.cjs's adapter-header-contract checks, install.js
structural-wiring guards with no exported symbol, AST-parse fixture
inputs, etc.) — each marker cites an existing repo-sanctioned category
from CONTRIBUTING.md's allow-test-rule exception table.

Also converts two try/finally test bodies (introduced during this same
migration) to the required t.after() cleanup pattern per CONTRIBUTING.md.

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

* chore(#3545): re-baseline effective-exemption ceiling to 81

The fold+hooks widening's own newly-detected sites are now suppressed by
site-scoped markers, moving them from invisible into the tightly-ratcheted
effective-exemption count. Ceiling rises from 10 to 81 (the exact measured
high-water mark, grace unchanged at 2) — a deliberate, measured re-baseline
per the widening working as intended, not an ordinary ceiling bump.

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

* fix(#3545): use canonical allow-test-rule category tokens

4 markers added during migration cited an issue ref correctly but didn't
use one of CONTRIBUTING.md's seven recognized category tokens, unlike
every other marker in this change. Cosmetic only — same suppression
lines, same effective/live counts (81/81, 0 live).

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

* fix(#3545): correct stale phase-artifact path in test comment

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

---------

Co-authored-by: sim <sim@local>
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

tests/worktree-safety.test.cjs

@@ -5490,6 +5490,10 @@ describe('install.js guard for gsd-worktree-path-guard.js', () => {
   before(() => {
     // ADR-857 phase 5f-1b: hook registration moved to runtime-hooks-surface.cts.
     // Concatenate both sources so structural assertions find patterns in either file.
+    // allow-test-rule: structural-implementation-guard (#3545) — structural install.js
+    // guard; install.js has side effects on require and no exported symbol for hook-registration wiring;
+    // every src.includes()/indexOf() and block.includes() call below traces
+    // back to this read
     const installSrc = fs.readFileSync(INSTALL_SRC, 'utf-8');
     let hooksSurfaceSrc = '';
     try { hooksSurfaceSrc = fs.readFileSync(HOOKS_SURFACE_SRC, 'utf-8'); } catch { /* ok */ }