Fix NotificationCenter database path on newer macOS

[franklinho]

Summary

• Prefer the newer macOS group.com.apple.usernoted NotificationCenter database path when it exists.
• Fall back to the legacy com.apple.notificationcenter database path.
• Await the existing async DB existence check so startup reports missing notification DBs correctly.

Schema verification

• Verified on macOS 26 that ~/Library/Group Containers/group.com.apple.usernoted/db2/db contains the same record and app table shape expected by the existing TypeORM entities.
• record columns: rec_id, app_id, uuid, data, request_date, request_last_date, delivered_date, presented, style, snooze_fire_date.
• app columns: app_id, identifier, badge.
• Smoke-queried real rows from the new DB path, including com.apple.mobilesms.

Testing

• Ran git diff --check origin/development...HEAD.
• Confirmed origin/development does not currently contain the group.com.apple.usernoted path fix.