Read only the type and credential when updating a connector - #1627

Summary

Saving a connector (for example PUT /api/connectors/:id/env-vars) loaded the whole connector twice, with every tool, resource and prompt. Sentry flagged it as an N+1 query (ANYTHINGMCP-CLOUD-BACKEND-E, sampled on 11-10). The second load is in ConnectorsService.update(), which only needs the connector's type and its stored credential.

Changes

• update() reads { type, authConfig } with a select instead of calling findById (which includes tools, resources, prompts and server links).
• A missing connector still throws the same NotFoundException.

Type

• Bug fix
• New feature
• Documentation
• Refactoring
• Performance improvement
• Other (describe below)

Testing

• Added/updated unit tests: connectors.service.auth-status.spec.ts checks the narrow select and the 404 for an unknown id; the existing auth-status and bearer tests still cover what existing is used for.
• Tested manually (describe steps below)
• No tests needed (explain why)

Backend CI runs the suite (the local Prisma client in my checkout is out of date).

Checklist

• My code follows the existing code style
• I have tested my changes locally
• I have updated documentation (if applicable)
• All existing tests pass (npm test) (in CI)
• This PR has a descriptive title

Cloud and self-hosted behave the same; no API or schema change.

Related Issues

Sentry ANYTHINGMCP-CLOUD-BACKEND-E