FEATURE REQUEST: [PLM] Add Ability to Set Category (group-title) Override for Parent Stations

[frigginbrownie]

When generating M3Us, Playlist Manager will take the group-title from the source M3U for a channel. Depending on how the group-title was set in source M3U, this can result in a playlist with dozens/hundreds of groups, many with 1-3 channels each.

In order to consolidate them, the user should be able to set a custom category via a text field, which would update the group-title tag (and perhaps the tvc-guide-categories tag?) in the generated M3U.

Alternatively/additionally, a toggleable setting to not copy the group-title to a generated playlist could be considered. This could be extended to not copying tvg-logo and tvg-description as well.