docs: backfill v2.4.3 release notes + plugin.json description

- README "Recent Updates": v2.4.3 entry covering worktree-aware git-ops,
  push-gate skill, worktree-boundaries rule, auto-skill visibility fix,
  push-gate regex bug repair (everything since v2.4.1).
- README inventory tagline: 5 styles → 13 styles, +6 rules
- plugin.json description: 68 → 69 skills, 5 → 6 rules

No version bump — plugin.json stays at 2.4.3 (matches origin).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "claude-mods",
   "version": "2.4.3",
-  "description": "Custom commands, skills, and agents for Claude Code - session continuity, 23 expert agents, 68 skills, 3 commands, 5 rules, 4 hooks, 13 output styles, modern CLI tools",
+  "description": "Custom commands, skills, and agents for Claude Code - session continuity, 23 expert agents, 69 skills, 3 commands, 6 rules, 4 hooks, 13 output styles, modern CLI tools",
   "author": "0xDarkMatter",
   "repository": "https://github.com/0xDarkMatter/claude-mods",
   "license": "MIT",