feat(protocols): add logging socket closing

lib/core/network/protocols/httpwsProtocol.js

@@ -313,12 +313,26 @@ class HttpWsProtocol extends Protocol {
       return;
     }
 
+    const reason = Buffer.from(message || "").toString();
+
+    // This hack is only here to indicate that uWebSockets killed the connection early
+    // because the received payload exceeded the configured threshold.
+    if (
+      code === 1006 &&
+      typeof reason === "string" &&
+      reason.startsWith("Received too big message")
+    ) {
+      global.kuzzle.log.error(
+        `[${connection.id}] connection closed: payload exceeded the threshold`,
+      );
+    }
+
     if (debugWS.enabled) {
       debugWS(
         "[%s] received a `close` event (CODE: %d, REASON: %s)",
         connection.id,
         code,
-        Buffer.from(message || "").toString(),
+        reason,
       );
     }
     this.entryPoint.removeConnection(connection.id);