Fix timer persistence and desktop reliability

[Aucannot]

Summary

• make Tauri timer transitions durable, validate command inputs, restore sessions from wall-clock time, and cache auto-end settings
• persist the native macOS timer across relaunches, compute real daily statistics, and make quit/build/signing behavior reliable
• prevent unsaved configuration from starting a mismatched timer, tighten Tauri permissions, and remove unused UI/dependencies
• improve compact/expanded UI accessibility and add frontend, Rust, and Swift regression coverage

Root cause

Timer state was maintained mainly in process memory, so relaunches and delayed ticks could lose or distort session progress. Configuration and lifecycle commands also lacked consistent validation and persistence boundaries. The native client had the same wall-clock/persistence gaps, while the build and UI layers retained unused permissions, dependencies, and components.

Validation

• npm test — 5 frontend, 3 Rust, and 3 Swift tests passed
• npm run build
• npm run tauri build -- --debug
• npm run mac:native:build
• npm audit — 0 vulnerabilities
• bash -n native-macos/scripts/build-app.sh
• strict codesign --verify --deep --strict for both generated macOS app bundles
• git diff --check

Notes

The generated bundles use ad-hoc signing for local verification. Developer ID signing and notarization still require the corresponding Apple credentials/profile.