feat(hookify): load rules from ~/.claude global location

[watarus]

Summary

• hookify currently only loads rules from <cwd>/.claude/hookify.*.local.md, so a rule has to be re-created in every project.
• This PR also reads ~/.claude/hookify.*.local.md so a rule can be defined once and apply across every project.
• Same-named rules: project-local overrides global, so a project can still override a global rule. Existing project-only setups are unaffected (the new path is purely additive).

Behavior

• New search order: ~/.claude/hookify.*.local.md (global) merged with <cwd>/.claude/hookify.*.local.md (project-local).
• Dedupe is by name field, project-local last-write-wins.
• When cwd == $HOME the two globs hit the same files; those are filtered via os.path.abspath so each file is only loaded once.
• All existing error handling / event filtering / enabled filtering is preserved.

Test plan

• Smoke test: global-only rule, project-only rule, and same-named rule in both → project-local wins, no duplicates
• Smoke test: cwd == $HOME → no double-loading
• Existing project-only setups continue to behave unchanged (no global file present)

🤖 Generated with Claude Code