0.10.0: Business Credit Usage

• Added Business-account credit usage support for responses that do not expose Codex rate-limit windows. Impact: the statusline now shows rounded remaining credit percentage and an optional reset countdown while preserving existing rate-limit displays when both forms are available.
• Scheduled credit reset countdown redraws at their exact display boundaries and retained credits-only reports in the active cache. Impact: credit status remains locally responsive between API refreshes without displacing model-specific quota windows.