MCP `quotas` stops telling agents quotas are unenforced: each key says what it bounds #6251

The quotas tool's description is "Per-account repo and app quotas (unenforced)." and src/http/api.ts above GET /api/v1/admin/settings says "Nothing enforces them yet", but src/settings/quotas.ts shows all six keys are asked (repos on create/fork/copy, apps, storage on push, live previews, concurrent runs and checks, never of a forge admin). Being plain about limits is trust.

Done:

• [ ] The tool's description and doc name the six keys and what each bounds, in the words of src/settings/quotas.ts's header, and say a forge admin is never limited.
• [ ] The stale comment in src/http/api.ts is corrected.
• [ ] A test asserts the tool's description does not contain "unenforced" and names every key in QUOTA_KEYS.

Files: src/http/mcp/tools/quotas.ts, src/http/api.ts (comment), a test.

Parked by the steward, 2026-10-26 (owner: "get us unclogged now then resume everything else"). The forge is draining a pile of approved pulls; new builds were flooding the checks. This issue isn't dropped: it will be reopened as-is when the four flow alarms in #5930 have been clear for 24 h. The list is kept in the steward's parked-2026-10-26 file.