follow-up to #3315 / #3366

The fix was applied one layer too late

#3366 retired 4 hooks, so two prose counts in the docs went stale. They were corrected in the generated pages rather than the sources those pages are built from, which means every npm run build put the wrong numbers back. Nothing went red, because the drift gate does not watch that directory.

The two layers

Ground truth: bin/count-hooks.sh → GLOBAL=149 TOTAL=215.

  SOURCE                                                  stale
  src/skills/doctor/references/hook-validation.md         152 global entries
  src/skills/setup/references/readiness-scoring.md        218 hooks active
      │
      │   npm run build   (overwrites, every time)
      ▼
  GENERATED                                               correct, and discarded
  docs/site/content/docs/reference/skills/doctor.mdx      149 global entries
  docs/site/content/docs/reference/skills/setup.mdx       215 hooks active

Why CI stayed green

Two independent gates, and the file falls between them.

ci.yml:77   GENERATED=(plugins/  src/hooks/dist/  README.md  docs/site/lib/generated/)
                                                        docs/site/content/ is NOT here

test-docs-site-drift.mjs   TOTAL_CLAIM matches:  "OrchestKit's 219-hook system"
                           does NOT match:       "OrchestKit uses 152 global hook entries"
                                                 "218 hooks active"

The build-drift gate would have caught a rewritten committed file, but only inside four watched directories. The docs-site drift gate would have caught a stale plugin-wide total, but its pattern requires the OrchestKit's N-hook phrasing. Each gate is individually reasonable; the overlap is where this lives.

What this change does

Re-stamps both sources to 149 / 215, matching count-hooks.sh.
Rebuilds, so the generated pages keep the values they already had.
Makes npm run build idempotent: a second run leaves docs/site/content/ clean. That is the falsifiable part — before this change a second build always produced a diff.

Deliberately not done here: widening the drift gate to cover docs/site/content/, or loosening the TOTAL_CLAIM pattern. Both are real gaps and both are pre-existing, but changing a required gate's scope is its own decision with its own blast radius, not a rider on a two-line fix.

Check whether a doc number lives in the source or the build output.