0.0.1: Simplify quota retrieval and separate account from usage values

Read the single supported OpenAI provider directly instead of maintaining an adapter registry, parallel aggregation, and duplicate error handling. Construct the RPC response at its boundary while preserving quota data, validation errors, cancellation, and cleanup.

Use native Map.groupBy without copied group metadata. Remove redundant date and width helpers and the finite-number guard already enforced by Zod. Add a middle-dot separator between the account label and quota windows, and update the README example.

Verification: ESLint, TypeScript, tracked-file Prettier checks, package dry-run, and git diff --check passed. In-memory comparisons matched 28 server and 31 footer scenarios before the requested separator change; a focused formatting assertion confirmed that change. The full check script is blocked by a pre-existing permission error reading .serena/project.yml.