BlogGen Connector v1.1.6 — Encrypted Social Tokens + Update Safety Improvements

This client-side connector update strengthens the security model introduced in v1.1.4/v1.1.5.

Included:
- Facebook Page and Instagram/Meta access tokens are encrypted locally before being stored in WordPress options.
- Existing plain Meta tokens are migrated to encrypted storage for site administrators.
- Token fields show saved/ending details without exposing full credentials.
- Clear token controls added for Facebook and Instagram.
- Secure social profile reports encrypted token readiness to the Hub without exposing tokens.
- Hub-managed update requests are still opt-in.
- Update downloads are restricted to the configured Hub manifest host.
- Hub-managed update requests require a SHA-256 package checksum.
- Last update attempt/result/source fields are stored for diagnostics.

Setup:
1. Install this connector on the client WordPress site.
2. Go to Tools > BlogGen Connector.
3. Confirm remote publishing is enabled.
4. Paste Meta social credentials only on the client site, not in the Hub.
5. Enable Hub-managed updates only if the client wants BlogGen Hub to request connector updates.
