This replaces the are-you-sure dialog and also shows up when using
/-commands.

Closes: https://github.com/Nheko-Reborn/nheko/issues/239

# Previous commits:
#   e390c398 Allow to specify reason for removed message
#   5949173b Add function to force focus on InputDialog input field
#   9482ac4e Allow explicit selection of SSO method
#   ab05e2d8 Mobile message input (#962)

It seems like handling the message in a blocking manner is a no-go. I
have no idea how to fix that, so just use a queued connection for now...
(ASAN does not cooperate and just hides the crash D:)

fixes #842

Either by accepting an invite or manually using /converttodm and revert
with /converttoroom.

fixes #317

Fixes messages in room flickering and being stuck

fixes #760
relates to #770
relates to #789

- Fixes scrolling to an event not being reliable
- Adds new /goto command that can open URLs, go to events, or go to message indexes.
- Refactored ChatPage::handleMatrixUri() to contain the handling originally in Nheko::openLink(), and makes it return a boolean based on whether the URL was handled internally or not.

- Now scrolls entire profile instead of only device list, improving the experience on smaller screens
- Fixed centering of room name
- Allow profile to be sized smaller to match the new scrolling behavior
- Silenced warning about room being null for global profiles
- Matrix URLs now open global profiles instead of room-specific profiles if the user is not in the currently opened room
- Opening global profile from room specific profile now uses openGlobalUserProfile function instead of reinventing the wheel