docs: add security policy and deployment guide

- Add SECURITY.md with vulnerability reporting process
- Add comprehensive deployment guide (docs/deployment/index.md)
- Generate uv.lock for reproducible builds
- Update audit rules to check correct deployment path
- Remove Node.js dependency, use Tailwind CLI standalone

Resolves audit warnings:
- THIRD-DEP-001: Dependency lock file
- DOC-SEC-001: Security policy
- DOC-OPS-001: Deployment documentation

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

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

scripts/validate_audit.py

@@ -463,12 +463,12 @@ class AuditValidator(BaseValidator):
             )
 
         # Check deployment documentation
-        deploy_doc = self.project_root / "docs" / "guides" / "deployment.md"
+        deploy_doc = self.project_root / "docs" / "deployment" / "index.md"
         if not deploy_doc.exists():
             self.add_warning(
                 "DOC-OPS-001",
                 "Deployment documentation recommended",
-                "docs/guides/deployment.md",
+                "docs/deployment/index.md",
             )
 
     # ==================