Turns out a lot of the typescript warnings about improper warnings were correct. TypeScript appears to be pulling in two copies of the js-sdk when we do this, which can lead to type conflicts (or worse: the wrong code entirely). We fix this at the webpack level by explicitly importing from `src`, but some alternative build structures have broken tests because of this - jest ends up pulling in the "wrong" js-sdk, breaking things.
This adds support for an admin-configured message in config.json to be shown in
the report content dialog to allow linking to community rules, etc.
Fixes https://github.com/vector-im/riot-web/issues/11992
