feat(ultraplan-local): v2.3.1 — qualified slug convention for cc-architect-catalog

Resolves v2.3.0 dogfood collision: skill-factory produced a
specialized hooks-pattern.md draft that would have overwritten the
generic seed. Qualified slugs let one feature host multiple named
patterns at different abstraction levels.

Slug convention: <cc_feature>[-<qualifier>]-<layer>.md. Unqualified =
canonical baseline. Qualified = sub-pattern (e.g., hooks-observability-
pattern.md) that does not displace the baseline.

Changes:
- SKILL.md: slug convention section, coverage-table qualified column,
  matcher logic for N patterns per feature, modification rules cover
  qualified-vs-canonical choice and collision handling.
- feature-matcher: catalog map is cc_feature -> {layer -> [skills]};
  selection rules (baseline by default, qualified when justified,
  multi-skill when non-overlapping); supporting_skill accepts list.
- gap-identifier: adds pattern_count[cc_feature] to coverage audit.
- architecture-critic: supporting-skill verification — every cited
  skill name must exist in the catalog (blocker severity).
- First qualified skill: hooks-observability-pattern.md (promoted from
  .drafts/, source ai-psychosis/README.md, ngram-overlap 0.01).
- Version bump 2.3.0 -> 2.3.1 across plugin.json, badges, table, root
  CLAUDE.md, CHANGELOG.

Non-breaking: existing unqualified slugs keep working, no cc_feature
taxonomy changes, hallucination gate unchanged.

README.md

@@ -61,7 +61,7 @@ Key commands: `/config-audit posture`, `/config-audit feature-gap`, `/config-aud
 
 ---
 
-### [Ultra {brief | research | architect | plan | execute} - local](plugins/ultraplan-local/) `v2.3.0`
+### [Ultra {brief | research | architect | plan | execute} - local](plugins/ultraplan-local/) `v2.3.1`
 
 Deep requirements gathering, research, Claude Code feature matching, implementation planning, self-verifying execution, and skill-factory authoring with specialized agent swarms, adversarial review, IP-hygiene scoring, and failure recovery.
 
@@ -76,7 +76,7 @@ Five core commands plus an authoring command, one pipeline with clear division o
 
 All artifacts land in one project directory: `.claude/projects/{YYYY-MM-DD}-{slug}/` contains `brief.md`, `research/NN-*.md`, `architecture/` *(v2.2)*, `plan.md`, `sessions/`, and `progress.json`. `--project <dir>` works across `/ultraresearch-local`, `/ultra-cc-architect-local`, `/ultraplan-local`, and `/ultraexecute-local`.
 
-v2.3 (non-breaking) ships the skill-factory Fase 1 MVP: `/ultra-skill-author-local` plus four supporting agents (1 opus orchestrator + 3 sonnet workers) and `scripts/ngram-overlap.mjs` (pure Node stdlib, word-5-gram containment + longest-run secondary signal, calibrated against three source/draft fixture pairs). Catalog growth is now tractable without touching the architect's hallucination gate. Non-goals stay explicit: no automation, no batch, no decision-layer skills, no remote sources — manual `mv` from `.drafts/` to catalog root is the promotion mechanism.
+v2.3 (non-breaking) ships the skill-factory Fase 1 MVP: `/ultra-skill-author-local` plus four supporting agents (1 opus orchestrator + 3 sonnet workers) and `scripts/ngram-overlap.mjs` (pure Node stdlib, word-5-gram containment + longest-run secondary signal, calibrated against three source/draft fixture pairs). Catalog growth is now tractable without touching the architect's hallucination gate. Non-goals stay explicit: no automation, no batch, no decision-layer skills, no remote sources — manual `mv` from `.drafts/` to catalog root is the promotion mechanism. v2.3.1 adds a qualified-slug convention (`<cc_feature>[-<qualifier>]-<layer>.md`) so one feature can host multiple named patterns at different abstraction levels without displacing the baseline — resolved a collision surfaced in v2.3.0 dogfood.
 
 v2.2 (non-breaking) adds the optional `/ultra-cc-architect-local` step between research and planning. The architect phase is backed by a versioned catalog skill (`cc-architect-catalog`) with 10 seed entries across three layers (reference, pattern, decision). Gaps are captured as issue-ready drafts so the catalog grows from real usage rather than speculation. `/ultraplan-local` auto-discovers the architecture note — existing pipelines keep working unchanged.