Post only the transcript, not the recording file

[dennisklappe]

Recording and transcription both post into the call thread. The video dwarfs the transcript, so for a team that only wants searchable text the storage cost is mostly waste.

A setting to keep the transcript and drop the recording. The subtlety is that the transcript is produced from the recording, so the file has to exist first and then be removed, not never created. The recording post itself is a single CreatePost in server/bot_api.go.

[dennisklappe]

Blocked on a real limitation, recording it here so the next person does not rediscover it.

The plugin API has no file deletion. The full list of Delete* methods on the plugin API is channels, channel members, commands, ephemeral posts, groups, group members, group syncables, OAuth apps, posts, preferences, property fields and values, teams, team members and users. No files.

So a plugin can suppress the recording post, which keeps the call thread clean, but it cannot remove the mp4. Since the point of this issue was storage, that would be half a feature wearing the name of a whole one.

Doing it properly means deleting outside the plugin, where the file actually lives: either the job service stops keeping the recording once transcription succeeds, or something server side removes files no post references. Both are bigger than a plugin setting.

Leaving this open rather than shipping the half that does not save anything.