Add selectable Voxtype and Superwhisper dictation (#14552)

* Add selectable dictation backends

* Move dictation migration after repository priority update

* Extract backend-specific dictation installers

* Keep dictation installer dispatcher executable

* Call dictation backend installers directly

* Drop legacy Superwhisper migration and runtime cleanup

* Separate dictation defaults from generic recording protocol

* Add backend-specific dictation removers

* Preserve existing Voxtype selection during upgrade

* Make dictation backend selection safe and retryable

* Show the dictation indicator only for selected Voxtype

* Allow switching away from stopped Superwhisper

* Remove the built-in bar dictation indicator

* Store default dictation selection under defaults

* Rename dictation backend selector to use

* Move dictation removers into their own menu category

default/voxtype/config.toml

@@ -11,7 +11,7 @@
 state_file = "auto"
 
 [hotkey]
-# Hotkey is configured in Hyprland. Default is Super + Ctrl + X
+# Hotkeys are configured in Hyprland: hold Right Alt or F9, or toggle with Super + Ctrl + X.
 enabled = false
 
 [audio]