[Bug] Anthropic API Error: Account credit balance validation failing with HTTP 400 despite available credits

**Bug Description**
Evidence to paste into the ticket:
- Organization: 6f8c1247-b44f-478b-b12b-ad61437594f0
- Workspace: Default (wrkspc_01VQLazKdXNeiKgtrAY1JMbo)
- Request IDs: req_011CedHsyqsa1f4oN2FoZQmP, req_011CedHhj1NAdfQJUkn112MY
- Symptom: Console shows a $100 credit balance; every API call returns HTTP 400 invalid_request_error — "Your credit balance is too low." A newly minted Default-workspace key reproduces it, and even the no-cost count_tokens endpoint returns the same error, which points at an account-level block rather than balance arithmetic.

**Environment Info**
- Platform: darwin
- Terminal: xterm-256color
- Version: 2.1.252
- Feedback ID: b6b845c6-b70b-46d2-abe3-b0504136e62b

**Errors**
```json
[]
```

Start by reviewing the supplied request IDs, organization and workspace identifiers, console balance, and the no-cost count_tokens reproduction. The issue provides no repository file or test to inspect; done would require confirming the account-level cause and documenting a resolution or actionable repository change.

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