fix: address v3 runtime UX reports

[nullxnothing]

Summary

• Force DAEMON shutdown on app close and SIGINT/SIGTERM so dev sessions exit cleanly on macOS
• Hide the terminal pane when no project exists instead of showing an unusable empty panel
• Make Arena reachable with explicit inactive/status messaging when Pro access is not active
• Bump package version to 3.0.1

Validation

• pnpm run typecheck
• pnpm test