Refactor Claude Code settings to use template pattern

- Create .claude/settings.json as project-wide template
- Untrack .claude/settings.local.json for local overrides
- Add .claude/settings.local.json to .gitignore
- Add .claude/README.md documenting the setup

This allows:
- Project defaults versioned in git
- Local customization without conflicts
- Clean separation of shared vs personal settings

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.gitignore

@@ -16,4 +16,7 @@ NPM/data/*.json
 sqlite/*.db
 sqlite/*.sql
 
-tests/
+tests/
+
+# Claude Code local settings
+.claude/settings.local.json