fix: enhance MCP token handling (#14483)

fix #14475 

#### PR Dependency Tree


* **PR #14483** 👈

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

## Release Notes

* **New Features**
* Enhanced MCP server token management with improved security—tokens now
display only once with redaction support.
* Updated token creation and deletion workflows with clearer UI state
controls.
* Added tooltip guidance when copying configuration with redacted
tokens.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/core/src/modules/cloud/services/access-token.ts

@@ -24,7 +24,7 @@ export class AccessTokenService extends Service {
   isRevalidating$ = new LiveData(false);
   error$ = new LiveData<any>(null);
 
-  async generateUserAccessToken(name: string) {
+  async generateUserAccessToken(name: string): Promise<AccessToken> {
     const accessToken =
       await this.accessTokenStore.generateUserAccessToken(name);
     this.accessTokens$.value = [
@@ -33,6 +33,8 @@ export class AccessTokenService extends Service {
     ];
 
     await this.waitForRevalidation();
+
+    return accessToken as AccessToken;
   }
 
   async revokeUserAccessToken(id: string) {