Include reported username in final message after marking a report as invalid

Currently after marking a report as invalid/ignored details of the reported user are removed from the room completely. The usual reason I end up doing this is because its not in a room we control. Also if one person marks it as invalid, the others in the management room have no idea of the reported user unless they saw the messages before this was done. It would be useful to be able to still have some history of the reported user in case in the future we come across them in a room we do control

A solution to this could be to extend the current message
`Report by user $reporting-user has been classified as invalid`
to include the reported username something like
`Report by user $reporting-user of $reported-user has been classified as invalid`

Search the TypeScript source for the current invalid/ignored report message and inspect the surrounding report-handling entry point. Update the final message to retain both the reporting and reported usernames, then run the relevant report or moderation tests if present and verify the resulting room message.

Written by the indexing model from the issue text.