Change Details

Part of [ENG-9604](https://linear.app/comm/issue/ENG-9604/update-the-backup-handler-lifecycle-for-minimal-version-of-backup) but only for staff. Starting Rust thread responsible for uploading Backup. Right now it will be used to upload User Keys only, but in future will be used for User Data and logs. Adding alert to log if anything went wrong. Depends on D14048, D14050

Part of [ENG-9604](https://linear.app/comm/issue/ENG-9604/update-the-backup-handler-lifecycle-for-minimal-version-of-backup) but only for staff. Starting Rust thread responsible for uploading Backup. Right now it will be used to upload User Keys only, but in the future, it will be used for User Data and logs. Adding an alert to log if anything went wrong. Depends on D14048, D14050

Part of [ENG-9604](https://linear.app/comm/issue/ENG-9604/update-the-backup-handler-lifecycle-for-minimal-version-of-backup) but only for staff. Starting Rust thread responsible for uploading Backup. Right now it will be used to upload User Keys only, but in the future, but in futureit will be used for User Data and logs. Adding an alert to log if anything went wrong. Depends on D14048, D14050