deprecate `managementRoom` config option and provide "managed" management room instead

[Gnuxie]

Our documentation has quite a complicated and length diatribe about e2ee management room being unsupported. In the advent of #1022, this is really quite serious.

Instead Draupnir should warn that e2ee management room is not supported and draupnir may refuse to start in a future release.

Anyone on a normal management room will get migrated to a "managed" management room like the appservice has and the room will become inoperable if e2ee is turned on.

Setting up a draupnir in bot mode will require providing an mxid via a cli option and creating the management room for them. Which avoids all the complicated documentation reading.

context: https://matrix.to/#/!IaWNErZAgQUhGqJXjX:matrix.org/%24sDqKqPS9R9lJ_un4Via9jSF5eeplLCpV5JAw36b1vDo?via=matrix.org&via=breadpirates.chat&via=envs.net

[FSG-Cat]

Cat should add that Cats personal this wont be painful to write in mdad logic way of achiving it is via config option and having this mxid we provide to allow bootstrap to be in the config permanently.

Having a CLI option be one way to do things is ofc also workable its just for the mdad situation its easiest from a workflow and code perspective to have it be a config option that permanently lives in the config but is only "required" whenever the management room is missing.

Edit: i should emphasise that while its workable it would be a royal pain in the arse for me to personally implement if i can even implement it without it being SUPER levels of jank.