release: v5.12.4 — "Rooted rules" (M-BUG-9: RUL resolves rule glob against the rule's own project root)

Version-sync for the M-BUG-9 fix (code already in 18af5a2):
- plugin.json 5.12.3 -> 5.12.4
- README version badge -> 5.12.4, tests badge 1305 -> 1307, new version-history row
- CHANGELOG [5.12.4] section

checkReadmeBadges: passed:true (tests 1307, scanners 16, commands 21, agents 7, hooks 4 — all
match filesystem). Full suite 1307/0. Frozen v5.0.0 + default-output snapshots byte-stable
(the fix is a no-op when projectRoot === targetPath; RUL appears in no snapshot).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EnUvKEqyEa1m9gy6Aqhdqq

.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "config-audit",
   "description": "Multi-agent workflow for analyzing, reporting, and optimizing Claude Code configuration across your entire machine",
-  "version": "5.12.3",
+  "version": "5.12.4",
   "author": {
     "name": "Kjell Tore Guttormsen"
   },