fix(mcplocal): thread client bearer into per-upstream McpdClient

Symptom: HTTP-mode mcplocal accepted the incoming mcpctl_pat_ bearer,
but every /api/v1/mcp/proxy call to mcpd for upstream discovery came
back with "Authentication failed: invalid or expired token" — because
those proxy calls were using the pod's DEFAULT McpdClient token,
which in a container with no ~/.mcpctl/credentials is the empty
string. The discovery GET was correct (explicit authOverride in
forward()), but syncUpstreams() then created McpdUpstream instances
bound to the original mcpdClient — so every tools/list to each
upstream went out with `Authorization: Bearer ` (empty) and mcpd's
auth hook rejected it.

Fix: add McpdClient.withToken(token) and have refreshProjectUpstreams
swap to `mcpdClient.withToken(authToken)` before handing the client to
syncUpstreams. This keeps the "pod has no identity" design: the token
used for downstream /api/v1/mcp/proxy calls is the caller's McpToken,
same as the one used for the initial discovery GET and for introspect.

Tested: project-discovery.test.ts + mcpd-upstream.test.ts pass. Next:
rebuild + roll the mcplocal image and retry LiteLLM probe.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/mcplocal/src/discovery.ts

@@ -46,7 +46,13 @@ export async function refreshProjectUpstreams(
     servers = await mcpdClient.get<McpdServer[]>(path);
   }
 
-  return syncUpstreams(router, mcpdClient, servers);
+  // Downstream upstream-proxy calls go through `mcpdClient` too. In HTTP-mode
+  // mcplocal the pod has no credentials of its own, so the default token on
+  // `mcpdClient` is an empty string — every /api/v1/mcp/proxy call would 401.
+  // Bind a per-request client with the caller's bearer so each McpdUpstream
+  // forwards the same identity that passed project discovery.
+  const upstreamClient = authToken ? mcpdClient.withToken(authToken) : mcpdClient;
+  return syncUpstreams(router, upstreamClient, servers);
 }
 
 /**

src/mcplocal/src/http/mcpd-client.ts

@@ -60,6 +60,16 @@ export class McpdClient {
     return new McpdClient(this.baseUrl, this.token, { ...this.extraHeaders }, timeoutMs);
   }
 
+  /**
+   * Create a new client with a different Bearer token. The HTTP-mode mcplocal
+   * pod has no credentials of its own — each incoming client request carries
+   * its McpToken, and this method is how we thread that token through to the
+   * McpdUpstream instances created during project discovery.
+   */
+  withToken(token: string): McpdClient {
+    return new McpdClient(this.baseUrl, token, { ...this.extraHeaders }, this.timeoutMs);
+  }
+
   async get<T>(path: string): Promise<T> {
     return this.request<T>('GET', path);
   }

src/mcplocal/tests/project-discovery.test.ts

@@ -13,6 +13,7 @@ function mockMcpdClient(servers: Array<{ id: string; name: string; transport: st
     forward: vi.fn(async () => ({ status: 200, body: servers })),
     withTimeout: vi.fn(() => client),
     withHeaders: vi.fn(() => client),
+    withToken: vi.fn(() => client),
   };
   return client;
 }