feat: Add GitHub Actions CI for PR protection

- Add CI workflow with Python (ruff lint, security tests) and UI (ESLint, TypeScript, build) jobs
- Add ruff, mypy, pytest to requirements.txt
- Add pyproject.toml with ruff configuration
- Fix import sorting across Python files (ruff --fix)
- Fix test_security.py expectations to match actual security policy
- Remove invalid 'eof' command from ALLOWED_COMMANDS

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

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

client.py

@@ -16,7 +16,6 @@ from claude_agent_sdk.types import HookMatcher
 
 from security import bash_security_hook
 
-
 # Feature MCP tools for feature/test management
 FEATURE_MCP_TOOLS = [
     "mcp__features__feature_get_stats",