feat: Add Offline Data & Security section with key info and rotation …

[Glam26]

Prioritizing Tool Usage
I have completed the task. Here's a summary of the work:

1. Created New Branch: Checked out feature/offline-data-security-ui.
2. Added Offline Data & Security Section: Modified app/settings.tsx to include an "Offline Data & Security"
   section underneath the protocol configuration.
3. Wired up Key Info: Read the state directly via keyManager.getKeyInfo() upon component mount to display a
   human-readable relative creation date (Created X days ago) and its rotation status (Healthy or Rotation Due).
4. Manual Rotation Action: Built a Rotate encryption key now button. Clicking the button brings up an explicit
   confirmation dialog informing the user that this process will clear the offline cache, keeping expectations
   accurate.
5. Rotation Logic: Called keyManager.rotateKey and supplied a reencrypt callback that invokes
   asyncStoragePersister.removeClient(). Providing this callback forces the rotation and properly clears the
   undecryptable legacy data rather than stranding it on disk.
6. Committed Changes: Committed the updates directly into the new branch following the requirement.

closes #169