[Release Track] Android permissions and alarm policy

[jjoonleo]

Handle Android manifest permissions, notification/exact-alarm UX, full-screen intent declaration prep, and final alarm/notification QA.

Recommended sub-issue order

1. [Release] Audit Android manifest permissions for release #442 (codex-ready) - [Release] Audit Android manifest permissions for release
2. [Release] Verify notification permission UX #443 (codex-ready) - [Release] Verify notification permission UX
3. [Release] Verify exact alarm permission UX #444 (codex-ready) - [Release] Verify exact alarm permission UX
4. [Release] Prepare full-screen intent declaration and justification #445 (manual) - [Release] Prepare full-screen intent declaration and justification
5. [Release] QA alarm and notification flows on Android #457 (blocked) - [Release] QA alarm and notification flows on Android

Codex thread guidance

• Take this parent issue as the thread entrypoint.
• Work through sub-issues in the recommended order unless a sub-issue is marked blocked or manual.
• For codex-ready sub-issues, implement or verify only that issue's scope.
• For blocked sub-issues, stop at the prerequisite and leave a status note instead of forcing closure.
• For manual sub-issues, prepare checklist/text/instructions when useful, but do not claim completion without the required human or console access.
• Do not modify issues outside this parent track unless the sub-issue explicitly says to coordinate with them.