feat(hooks): add rules-injector hook for .cursor/rules and .claude/rules support

Implements adaptive rule injection similar to Claude Code's rule system:
- Searches .cursor/rules and .claude/rules directories recursively
- Supports YAML frontmatter with globs, paths, alwaysApply, description
- Adaptive project root detection (finds markers even outside ctx.directory)
- Symlink duplicate detection via realpath comparison
- Content hash deduplication (SHA-256) to avoid re-injecting same rules
- picomatch-based glob pattern matching for file-specific rules

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

.gitignore

@@ -25,3 +25,5 @@ yarn.lock
 # Environment
 .env
 .env.local
+test-injection/
+notepad.md