fix: route API/WS calls to backend port 3001 in local dev

Detect localhost and redirect API calls and WebSocket
connections from frontend port (3000) to backend port
(3001). Production behavior (via nginx proxy) unchanged.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

services/frontend/src/lib/api/client.ts

@@ -11,8 +11,17 @@ export class ApiError extends Error {
 function getBaseUrl(): string {
   if (typeof window === "undefined") return "";
   const protocol = window.location.protocol.replace(":", "");
-  const host = window.location.host;
-  return `${protocol}://${host}`;
+  const hostname = window.location.hostname;
+  const port = window.location.port;
+
+  // In local dev, frontend (port 3000) proxies API calls to backend (port 3001)
+  if (hostname === "localhost" || hostname === "127.0.0.1") {
+    const apiPort = port === "3000" ? "3001" : port;
+    return `${protocol}://${hostname}:${apiPort}`;
+  }
+
+  // Production: nginx proxies /api/* to backend
+  return `${protocol}://${hostname}${port ? `:${port}` : ""}`;
 }
 
 export async function apiRequest<T>(

services/frontend/src/lib/ws/connection.ts

@@ -5,8 +5,17 @@ type WsEventCallback = (event: WsEvent) => void;
 function getWsUrl(): string {
   if (typeof window === "undefined") return "ws://localhost:3001/ws";
   const protocol = window.location.protocol === "https:" ? "wss" : "ws";
-  const host = window.location.host;
-  return `${protocol}://${host}/ws`;
+  const hostname = window.location.hostname;
+  const port = window.location.port;
+
+  // In local dev, WS server runs on port 3001 alongside the backend
+  if (hostname === "localhost" || hostname === "127.0.0.1") {
+    const wsPort = port === "3000" ? "3001" : port;
+    return `${protocol}://${hostname}:${wsPort}/ws`;
+  }
+
+  // Production: nginx proxies /ws/* to backend
+  return `${protocol}://${hostname}${port ? `:${port}` : ""}/ws`;
 }
 
 export class WsConnection {