- Add tools/php_syntax_check.sh (supports full scan + single-file mode)
- CI workflow now calls the shared script
- All 6 agents updated to reference the script
- CONTRIBUTING.md: add Pre-Commit Checks section
- Exclude src/bin/* (third-party stubs) from lint
New GitHub Actions workflow that runs on push/PR to main and weekly:
1. PHP Syntax Check: validates all src/*.php files with php -l
2. Semgrep Security Scan: runs php, security-audit, command-injection,
sql-injection, and xss rule packs against src/
SARIF results are uploaded to GitHub Code Scanning.