Change Details

[Part of ENG-1729](https://linear.app/comm/issue/ENG-1729/update-notifications-dialog-to-handle-threads-correctly) Sidebars are always displayed under their parent chat, so the distinction between Focused and Background doesn't make sense and the notification dialog is misleading. - Removes the third "Background" option - Removes the statements of "Living in Focused/Background tab" - Renames the title to "Thread notifications"

[Part of ENG-1729](https://linear.app/comm/issue/ENG-1729/update-notifications-dialog-to-handle-threads-correctly) Sidebars are always displayed under their parent chat, so the distinction between Focused and Background doesn't make sense and the notification dialog is misleading. - Removes the third "Background" option - Removes the statements of "Living in Focused/Background tab" - Renames the title to "Thread notifications" {F185336}

[Part of ENG-1729](https://linear.app/comm/issue/ENG-1729/update-notifications-dialog-to-handle-threads-correctly) Sidebars are always displayed under their parent chat, so the distinction between Focused and Background doesn't make sense and the notification dialog is misleading. - Removes the third "Background" option - Removes the statements of "Living in Focused/Background tab" - Renames the title to "Thread notifications" {F185336}