GH Copilot CLI subtracted 5% for one request with 6x multiplier instead of 2%

The $10/mo account allows 300 premium requests, which is 0.33% of quota each. The model I've selected (Claude Sonnet 4.5 6x) should have subtracted 1/300*6 2% but my quota usage went down from from 20% to 15% which is 5%.

Please return the 3% of quota!

No file, test, or code entry point is named in the issue. Start by reproducing one request on the $10/month plan with Claude Sonnet 4.5 at the 6x multiplier, then trace how the CLI calculates and displays quota usage. Done means the request reduces the reported quota by 2% rather than 5%, with coverage for this case.

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