Meeting customization

[edemaine]

Now that meetings have secret keys (#144), we can add meeting-specific customization:

• [ ] Setting default sort for a meeting
• [ ] Setting default Jitsi, Cocreate, etc. servers (#30)
• [ ] Default room template (#47)
• [ ] Add/remove custom tab types from TabNew? (e.g. disable games or other things we add support for that aren't always relevant)
• [ ] Locking down permissions (#65), e.g., prevent normal users from creating/archiving/unarchiving rooms or adding tabs?
• [ ] Defaults for additional interface settings (#132)

[mehtank]

Additional meeting-level settings [ possibly meta-configurable via Config options depending on how much customizability you want to enable on the main server vs self-hosted servers ]:

• [ ] Header icon
  • [ ] URL to image
  • [ ] Alternate dark-mode icon
  • [ ] Header icon width
  • [ ] Link
  • [ ] Hover tooltip
  • [ ] Favicon?
• [ ] Welcome
  • [ ] Custom inlined HTML added somewhere in the existing text
  • [ ] IFramed link replacing the welcome page altogether
• [ ] Chat infrastructure [ e.g. external RocketChat / Discord-via-titanembed / ?? ]
  • [ ] IFrameable URL to replace default top-level "meeting chat"
  • [ ] some way [ API calls? URL mangler? ] to create / refer to new room-level chats

[mehtank]

* Setting default sort for a meeting

The code for this already existed but wasn't accessible. This can now be set (via API, no UI yet) with d437c81 in #175