potential fix

app.py

@@ -395,3 +395,20 @@ async def validate(payload):
     except Exception:
         logger.exception("Failed to process PR #%d", pr_num)
         return {"status": "error", "reason": "processing failed"}
+
+
+# ---------------------------------------------------------------------------
+# Server startup
+# ---------------------------------------------------------------------------
+
+if __name__ == "__main__":
+    app = WebhooksServer(
+        ui=None,  # No UI, just webhook endpoint
+        webhook_secret=os.environ.get("WEBHOOKS_SECRET"),
+    )
+    app.add_webhook(validate)
+
+    # Start the server on port 7860 (HF Spaces default)
+    port = int(os.environ.get("PORT", 7860))
+    logger.info("Starting webhook server on port %d", port)
+    app.run(server_name="0.0.0.0", server_port=port)