fix: keep saved Pomodoro sessions paused on mobile startup

[martin-forge]

Problem

Opening the mobile app can automatically resume a saved Pomodoro session synced from another device, allowing an old session to run without a new start action.

Solution

Restore the saved session in a paused state on mobile. Keep the session available for the user to resume; desktop startup behavior is unchanged.

Testing

• Seven focused Pomodoro tests pass, including the mobile startup regression.
• npm run lint and npm run build:test pass.
• Reloaded the standalone build in a disposable Obsidian vault; no captured errors.
• GitHub CI: full test suite and build passed.

[martin-forge]

Withdrawing this proposal. Pausing every saved mobile session changes existing timer behavior; I haven't established a bug that justifies that default change. The task-edit, Calendar, OAuth and settings fixes remain independent.