feat(plugin): command metadata, scoped skills, local-tier support, layered hooks, Stop audit

Wave 3 - adoption hardening. Patterns adapted (in original prose, with
attribution) from MIT-licensed shanraisshan/claude-code-best-practice.

Commands (command/enhance-claude-md.md, command/sync-claude-md.md):
- Add allowed-tools / disallowedTools / argument-hint / when_to_use so the
  commands auto-suggest in the slash menu and avoid permission prompts.
- disallowedTools blocks WebFetch + WebSearch on both commands.
- Drop the previous broken hooks block (array-of-{matcher, commands} shape
  did not match canonical schema; was never firing).

Skills:
- skill/karpathy-guidelines/SKILL.md: paths: glob over 23 code-file
  extensions, so the guardrails auto-load only when editing source, not
  markdown or data.
- skill/SKILL.md: model: haiku, effort: medium, paths: scoped to CLAUDE.md
  + AGENTS.md + .claude/rules/*.md so validator/generator passes run
  cheaply without changing the user-facing model.

CLAUDE.local.md personal tier:
- skill/validator.py BestPracticesValidator now accepts filename=; any
  *.local.md basename waives the 150-line cap.
- hooks/validate-claude-md.py reads the exempt suffix from hooks-config.
- .gitignore covers CLAUDE.local.md, **/CLAUDE.local.md,
  .claude/settings.local.json, hooks/hooks-config.local.json.

Layered hook config:
- hooks/hooks-config.json: committed defaults
  (validateClaudeMd.enabled/maxLines/exemptFilenameSuffix/exitCodeOnViolation,
  stopAuditLine.enabled).
- hooks/validate-claude-md.py merges hooks-config.json +
  hooks-config.local.json key-by-key; honours enabled=false (silent
  exit 0), configurable cap, configurable exit code.

Stop audit hook:
- hooks/audit-claude-md.py walks the project tree, prints one stderr
  line: total tracked / OVER cap / near cap (>=80%). Respects
  stopAuditLine.enabled from config.
- hooks/hooks.json registers Stop event with matcher "".

Guardian fail-closed contract:
- agent/claude-md-guardian.md Safety & Validation section now explicitly
  requires Skill-tool invocation (no inline paraphrase of SKILL.md),
  abort on missing validated output, never auto-commit, and respect
  local hook config.

Verified (8/8 smoke tests):
- Both commands parse with new fields and no broken hooks block.
- karpathy paths: 23 globs, includes .py/.ts/.go/.rs.
- skill model=haiku effort=medium with CLAUDE.md path scope.
- Validator: *.local.md (300 lines) -> pass; CLAUDE.md (300) -> fail;
  legacy ctor without filename -> default behavior preserved.
- hooks-config.json valid; validateClaudeMd.enabled=true, maxLines=150.
- Hook validator: default rc=2 on bloated, rc=0 when local override
  disables it, rc=0 on *.local.md (exempt).
- Stop hook entry present; audit script: rc=0 with "5 CLAUDE.md tracked".
- Regression: large-fullstack root still 52 lines with chain imports.

skill/validator.py

@@ -66,18 +66,24 @@ class BestPracticesValidator:
         }
     ]
 
-    def __init__(self, content: str, project_context: Dict[str, Any] = None):
+    def __init__(self, content: str, project_context: Dict[str, Any] = None, filename: str = None):
         """
         Initialize validator with CLAUDE.md content.
 
         Args:
             content: Full text content of CLAUDE.md file
             project_context: Optional project context for advanced validation
+            filename: Optional path or basename. When the basename ends with
+                ``.local.md`` (e.g. ``CLAUDE.local.md``), the 150-line cap is
+                relaxed because the file is a personal/gitignored override
+                outside the chained team-shared tree.
         """
         self.content = content
         self.lines = content.split('\n')
         self.line_count = len(self.lines)
         self.project_context = project_context or {}
+        self.filename = filename or ""
+        self.is_local_override = self.filename.endswith('.local.md')
 
     def validate_all(self) -> Dict[str, Any]:
         """
@@ -112,6 +118,25 @@ class BestPracticesValidator:
         message = f"File length is appropriate ({self.line_count} lines)"
         severity = "info"
 
+        # CLAUDE.local.md (and any *.local.md sibling) is a personal,
+        # gitignored override outside the chained team-shared tree. Skip the
+        # 150-line cap — only flag underuse.
+        if self.is_local_override:
+            if self.line_count < self.MIN_LINES:
+                status = "fail"
+                message = f"Personal override is too short ({self.line_count} lines, minimum {self.MIN_LINES})"
+                severity = "low"
+            else:
+                message = f"Personal override ({self.line_count} lines, cap waived)"
+            return {
+                "check": "file_length",
+                "status": status,
+                "message": message,
+                "severity": severity,
+                "actual_value": self.line_count,
+                "expected_range": f"{self.MIN_LINES}+ lines (cap waived for *.local.md)",
+            }
+
         if self.line_count > self.MAX_RECOMMENDED_LINES:
             status = "fail"
             message = f"File exceeds maximum recommended length ({self.line_count} > {self.MAX_RECOMMENDED_LINES} lines)"