fix(#4546): deferred UAT follow-ups no longer block completion and promote to the backlog (#4769)

* test(#4546): failing-first tests for deferred uat follow-ups

* chore(#4546): regenerate derived lists for the deferred-promotion suite

The new verify-work-deferred-promotion suite changes the tests/ tree the
macOS conformance-tier classifier tracks and is a novel file under the
verify prefix in the test-file-count ratchet; both derived lists are
regenerated/registered per their own guards' instructions.

* fix(#4546): deferred uat follow-ups no longer block, and get promoted

Two halves of one disconnect (#1921's deferral design vs the completion
predicate):

- uat-predicate: the item parser now captures the block's reason: line
  alongside result:. A skipped item whose reason carries the
  verify-work writer's 'Deferred follow-up:' template is a deliberate
  deferral -- non-blocking, flagged deferred in the report. Quote-
  tolerant (the writer wraps the value) and case-insensitive. A
  reasonless skip, a non-deferral reason, pending/blocked/issue/
  failed/missing all still block, exactly as before.
- verify-work complete_session: when the Deferred Follow-Ups section is
  non-empty, offer to promote the items to a ROADMAP.md 999.x backlog
  entry reusing next.md's prior_phase_completeness entry shape, with a
  --files-scoped commit. Offer, not auto-mutation -- matches the
  workflow's interactive convention and next.md's own prompt style.

* chore(#4546): refresh compact-content benchmark baseline

verify-work.md grew (the #4546 deferred-follow-up promotion offer in
complete_session); the registered split's token counts moved with it.
Baseline recomputed with the script's own --write.

Emitted-Drift-Ack-Growth: verify-work.md — complete_session gained the deferred-follow-up promotion offer (detection, [P]/[K] choice, the next.md-shaped 999.x entry template, and the --files-scoped ROADMAP.md commit); the growth is the new contract text, not duplication

* fix(#4546): gate/audit agreement and review fixes for deferred follow-ups

- src/uat.cts categorizeItem: a skipped item carrying the deferred
  follow-up template reason now categorizes as 'deferred' (the category
  already existed for deferred-items.md entries) instead of being
  misfiled into the blocked families by keyword match -- the gate/audit
  agreement #3078-CR expects, restored in the permissive direction the
  #1921 design intends. Checked BEFORE the keyword families so '...
  on the release build next version' is not build_needed.
- verify-work.md promotion step: numbering scans for the smallest free
  999.n (count races + non-contiguous history), one backlog entry per
  deferred follow-up, ROADMAP.md-absent behavior specified, idea text
  newline-flattened, Deferred at placeholder harmonized with next.md.
- DEFERRED_REASON_RE: trust assumption documented (authoring contract,
  not a security boundary; non-matching spellings block fail-closed).
- tests: the property now drives evaluateUatPassed and derives
  expectations from the input spec (never restates the matcher),
  includes the no-result-line branch, and pins its seed; the parity
  test drops try/finally for the approved pattern, uses createTempDir,
  sites its allow-test-rule marker at the suppression site, and asserts
  the literal [P]/[K] choices.

* fix(#4546): close promotion-test docstring, drop fc replay-path misuse, refresh baseline

The final matrix run caught three defects in my own review-fix commit:
the parity test file's JSDoc was left unterminated (the whole file
parsed as one comment -- zero tests registered, hence the file-level
'test failed' the runner reported); fast-check's replay-path parameter
was misused as a label (invalid path at replay); and the workflow-text
ambiguity fixes re-drifted the compact-content benchmark baseline.

* docs(#4546): add Fixed changeset for deferred follow-up coverage

* docs(#4546): backfill changeset PR number

* fix(#4546): use the pattern seam escapeRegex for shape-marker matching

The hand-rolled metacharacter escape in the shape-marker assertion
tripped local/no-adhoc-regex-escape, whose named remedy this adopts.

---------

Co-authored-by: sim <sim@local>

gsd-core/workflows/verify-work.md

@@ -542,6 +542,42 @@ Commit the UAT file:
 gsd_run query commit "test({phase_num}): complete UAT - {passed} passed, {issues} issues" --files ".planning/phases/XX-name/{phase_num}-UAT.md"
 ```
 
+**If the UAT file has a non-empty `## Deferred Follow-Ups` section,** those items are currently visible only inside this phase's `*-UAT.md` — offer to promote them to the roadmap backlog so they stay visible at the project level (#4546; reuses the exact entry mechanism `next.md`'s `prior_phase_completeness` step uses for plans-without-summaries):
+
+```
+Deferred follow-ups recorded: {N}
+
+They currently live only in {phase_num}-UAT.md. Promote them to the ROADMAP.md backlog?
+
+  [P] Promote to ROADMAP.md 999.x backlog
+  [K] Keep them in the UAT file only
+
+Choice [K]:
+```
+
+(TEXT_MODE: present this as a plain-text numbered list per the text-mode convention and wait for the typed choice.)
+
+**If the user chooses [P]:**
+1. Compute the next backlog number: `{backlog_number}` = the smallest positive integer not already used by an existing `### Phase 999.{n}` heading in `.planning/ROADMAP.md` — scan the headings rather than counting them, since numbering may be non-contiguous. If `.planning/ROADMAP.md` does not exist, create it containing only a `## Backlog` section and use `1`.
+2. Append to that `## Backlog` section one backlog entry per deferred follow-up (each with its own `999.{backlog_number}` heading, incrementing per entry), with `test`/`idea`/`deferred_at` verbatim from the section's YAML and `{idea}` flattened to a single line (newlines → spaces — a multi-line response would corrupt the single-line entry; this mirrors `next.md`'s use of a slug for the same reason):
+
+```markdown
+### Phase 999.{backlog_number}: Follow-up — Phase {phase_num} deferred UAT follow-up: Test {test} (BACKLOG)
+
+**Goal:** Resolve the UAT checkpoint deferred during Phase {phase_num} verification
+**Source phase:** {phase_num}
+**Deferred at:** {date} during /gsd:verify-work {phase} session completion
+**Follow-ups:**
+- [ ] Test {test}: {idea} (deferred {deferred_at})
+```
+
+3. Commit the deferral record:
+```bash
+gsd_run query commit "docs: defer Phase {phase_num} UAT follow-ups to backlog" --files .planning/ROADMAP.md
+```
+
+**If the user chooses [K]:** continue to the summary unchanged — the deferred items remain in the UAT file's `## Deferred Follow-Ups` section.
+
 Present summary:
 ```
 ## UAT Complete: Phase {phase}