[FEATURE] Add a way to customize waybar modules.json with persistence over updates

[SamoutL]

Is your feature request related to a problem? Please describe. Relating to waybar pulseaudio module modification suggestion I just posted: waybar/modules.json file gets overwritten with ml4w updates. Currently there is no way for user to make persistent modifications to waybar modules. A way to make persistent changes would be nice (similar to hyprland custom.conf and separate user made .conf files).

Additional context Example of such waybar user modification in this issue.