feat(core): improve mcp management (#15221)

#### PR Dependency Tree


* **PR #15221** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added MCP credential management (create/reveal, list, rotate, revoke)
with expiration and status tracking.
* Introduced read-only vs read/write access modes, with read/write
tooling enabled only when permitted.
* Added workspace MCP credential configuration UI, including token
reveal and setup generation.
  * Added MCP credential GraphQL APIs to back the UI.
* **Changes**
* Replaced legacy access-token support with MCP credentials across
authentication and realtime updates.
* **Bug Fixes**
* MCP authentication now reliably rejects revoked, rotated, expired, or
disabled-user credentials.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/core/sync/gateway.ts

@@ -353,7 +353,7 @@ export class SpaceSyncGateway
 
   private attachPresenceUserId(client: Socket): string | null {
     const request = client.request as Request;
-    const userId = request.session?.user.id ?? request.token?.user.id;
+    const userId = request.session?.user.id;
     if (typeof userId !== 'string' || !userId) {
       this.logger.warn(
         `Unable to resolve authenticated user id for socket ${client.id}`