Codex Usage Widget 0.0.1

First public snapshot release.\n\nHighlights:\n- Floating macOS Codex usage tab that does not add a menu bar item.\n- CodexBarCLI-backed Session and Weekly usage display.\n- Resizable panel, opacity recovery, and distinct OP opacity HUD.\n\nVerification run before publishing:\n- swift test\n- TZ=UTC swift test\n- swift build -Xswiftc -strict-concurrency=complete\n- ./script/build_and_run.sh --verify\n- codesign --verify --strict --deep dist/CodexUsageWidget.app\n\nSHA256:\n81d522a87f3342c9f69c7ccb16e32aeed7bd879492f82c2b8dfa3d3135ab703b CodexUsageWidget-0.0.1-macos.zip