[ feature rq ] Basic moderation without privilege checking: redact message, ban user

[bkil]

Please support banning an abuser and removing their messages by a moderator.

Some use Matrix over a bridge as a daily driver but still have to pay the Element tax every once in a while for moderation.

[bkil]

As a stop gap minimal viable product, I would accept this:

• long pressing on a message to bring up a menu with an option to redact message and another option to ban sending user
  • redacting your own messages is desirable in general
• no filling of reason field
• no prior checking of moderator privilege within the room
  • having sufficient permission level for redacting events and banning respectively according to room version specific rules is complicated
  • optional hacky workaround: reveal these menu options globally using an advanced user setting
• pop up an error dialog if the client API returns forbidden