Add health reporting, container probe, and JNN channel support

epg/healthcheck.py

@@ -0,0 +1,16 @@
+"""Container probe: degraded service remains usable and passes the probe."""
+import os
+import sys
+import urllib.request
+
+
+def main():
+    try:
+        with urllib.request.urlopen(f'http://127.0.0.1:{os.environ.get("PORT", "1876")}/health', timeout=5) as response:
+            return 0 if response.status == 200 else 1
+    except Exception:
+        return 1
+
+
+if __name__ == '__main__':
+    sys.exit(main())