Add multi-service Docker setup, Postgres migrations, and messaging API cleanup

deployment/healthcheck.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+"""
+Simple health check script using built-in urllib
+Replaces curl dependency in Docker health checks
+"""
+
+import sys
+import urllib.request
+import os
+
+def main():
+    port = os.getenv('PORT', '8300')
+    url = f'http://localhost:{port}/health'
+
+    try:
+        with urllib.request.urlopen(url, timeout=10) as response:
+            if response.status == 200:
+                print("OK")
+                sys.exit(0)
+            else:
+                print(f"HTTP {response.status}")
+                sys.exit(1)
+    except Exception as e:
+        print(f"FAILED: {e}")
+        sys.exit(1)
+
+if __name__ == '__main__':
+    main()