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/app.module.ts

@@ -27,7 +27,6 @@ import { PrismaModule } from './base/prisma';
 import { RedisModule } from './base/redis';
 import { RateLimiterModule } from './base/throttler';
 import { WebSocketModule } from './base/websocket';
-import { AccessTokenModule } from './core/access-token';
 import { AuthModule } from './core/auth';
 import { BackendRuntimeModule } from './core/backend-runtime';
 import { CommentModule } from './core/comment';
@@ -209,7 +208,6 @@ export function buildAppModule(env: Env) {
       CalendarModule,
       TelemetryModule,
       CommentModule,
-      AccessTokenModule,
       QueueDashboardModule
     )
     // doc service and front service