Add v0.5.0: CCGS Skill Testing Framework, skill-improve, 4 new skills, director gate path fixes

- Add CCGS Skill Testing Framework: self-contained QA layer with 72 skill specs,
  49 agent specs, catalog.yaml, quality-rubric.md, templates, README, CLAUDE.md
- Add /skill-improve: test-fix-retest loop covering static + category checks
- Add 4 missing skills: /art-bible, /asset-spec, /day-one-patch, /security-audit
- Add /skill-test category mode (Phase 2D) with quality rubric evaluation
- Extend /skill-test audit to cover agent specs alongside skill specs
- Update all skill-test and skill-improve path refs to CCGS Skill Testing Framework/
- Remove stale tests/skills/ directory (superseded by CCGS Skill Testing Framework)
- Add director gate intensity modes (full/lean/solo) to gate-check and related skills

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/hooks/session-stop.sh

@@ -11,17 +11,17 @@ mkdir -p "$SESSION_LOG_DIR" 2>/dev/null
 RECENT_COMMITS=$(git log --oneline --since="8 hours ago" 2>/dev/null)
 MODIFIED_FILES=$(git diff --name-only 2>/dev/null)
 
-# --- Clean up active session state on normal shutdown ---
+# --- Archive active session state on shutdown (do NOT delete) ---
+# active.md persists across clean exits so multi-session recovery works.
+# It is only valid to delete active.md manually or when explicitly superseded.
 STATE_FILE="production/session-state/active.md"
 if [ -f "$STATE_FILE" ]; then
-    # Archive to session log before removing
     {
         echo "## Archived Session State: $TIMESTAMP"
         cat "$STATE_FILE"
         echo "---"
         echo ""
     } >> "$SESSION_LOG_DIR/session-log.md" 2>/dev/null
-    rm "$STATE_FILE" 2>/dev/null
 fi
 
 if [ -n "$RECENT_COMMITS" ] || [ -n "$MODIFIED_FILES" ]; then