[yudelevi]

Part 1 of #45, split so the behavior that is already live can ship now.

The SDK raises InsufficientBalanceError (with requested_records, max_affordable_records in the request's own size unit) for a 403 INSUFFICIENT_BALANCE, and the CLI prints it. The refusal shipped with discolike-platform !994, which is on platform main.

Commits are #45's four balance commits, cherry-picked onto current development unchanged. ruff clean, 942 tests pass; ty reports the same 4 diagnostics as development.

Docs: discolike-api-docs !49. Part 2 (free plan, no-credentials 401 object) is stacked on this branch.

Confidence Score: 5/5

This PR appears safe to merge.

Summary

Adds InsufficientBalanceError for 403 responses carrying INSUFFICIENT_BALANCE.

• The SDK names balance refusals and exposes their request details.
• CLI errors identify balance refusals and show affordable request size.

No actionable issues found. Review checks were based on code inspection; tests were not run.

_{Reviews (1) · Last reviewed commit: "docs(sdk): max_affordable_records is 0 w..." · Reviewed by Greptile}