* merge all changes to one commit of PR #11157 / #11226
* rename the new paged messages route
* rename event, move map-method to the Inbox schema, fix lint
* move `mapMessage`-call to `getUserInbox`
* revert schema.method back to a normal one
* load messages per conversation
* only sort ones in ui
* add contributor to message
* fix correct message layout/message
* mugenScroll on chatMessages
* fix lint, no mugen-scroll, use own scroll handler
* fix height / margin of modal + use button to load more
* fix tests
* user data from inbox
* style "load earlier messages"
* move mapMessage to the inbox api result / extract sentMessage of members-api-controller
* fix test back
* fix test
* keep last scroll position
* just set the Id of the returned message instead of all other properties
* fix add new messages (buttons were hidden) + load more
* item-mounted debounce to trigger the re-scrolling