fix: report combined local transport failures once

cocoscreator_projects/YouleNexus/assets/scripts/local-platform-login/local-login-transport.ts

@@ -14,6 +14,16 @@ interface LocalLoginTransportOptions {
   record: EvidenceSink;
 }
 
+/** ES2020 aggregate: retain originals before notifying a terminal observer once. */
+class LocalLoginTransportFault extends Error {
+  readonly errors: readonly unknown[];
+  constructor(errors: readonly unknown[]) {
+    super('Local login transport failed with an additional cleanup error');
+    this.name = 'LocalLoginTransportFault';
+    this.errors = Object.freeze([...errors]);
+  }
+}
+
 /** Local-only socket boundary; raw evidence precedes protocol decoding. */
 export class LocalLoginTransport implements Transport {
   private socket: WebSocket | null = null;
@@ -53,8 +63,7 @@ export class LocalLoginTransport implements Transport {
       try {
         this.options.record({ kind: 'transport-receive', data: event.data });
       } catch (error) {
-        this.stopWithFault(error);
-        throw error;
+        throw this.stopWithFault(error);
       }
       if (this.socket === socket) this.messageCallback?.(event.data);
     };
@@ -68,8 +77,7 @@ export class LocalLoginTransport implements Transport {
       try {
         this.options.record({ kind: 'transport-error', data: event });
       } catch (error) {
-        this.stopWithFault(error);
-        throw error;
+        throw this.stopWithFault(error);
       }
       if (this.socket !== socket || this.generation !== generation) return;
       // Invalidate before close: browsers may dispatch close after error.
@@ -93,8 +101,7 @@ export class LocalLoginTransport implements Transport {
       socket.send(frame);
       this.options.record({ kind: 'transport-send', data: frame });
     } catch (error) {
-      this.stopWithFault(error);
-      throw error;
+      throw this.stopWithFault(error);
     }
   }
 
@@ -115,17 +122,17 @@ export class LocalLoginTransport implements Transport {
   onMessage(callback: (frame: string) => void): void { this.messageCallback = callback; }
   onClose(callback: () => void): void { this.closeCallback = callback; }
 
-  private stopWithFault(error: unknown): void {
+  private stopWithFault(error: unknown): unknown {
     const socket = this.socket;
     this.socket = null;
-    const cleanupErrors: unknown[] = [];
+    const errors: unknown[] = [error];
     try {
       socket?.close();
     } catch (cleanupError) {
-      cleanupErrors.push(cleanupError);
+      errors.push(cleanupError);
     }
-    this.options.onFault(error);
-    // Preserve both independent failures, including non-Error thrown values.
-    for (const cleanupError of cleanupErrors) this.options.onFault(cleanupError);
+    const fault = errors.length === 1 ? error : new LocalLoginTransportFault(errors);
+    this.options.onFault(fault);
+    return fault;
   }
 }