matrix chat: replies for private conversations are announced to the sender instead of the recipient
Currently the matrix announcements for private messages work only partly:
- the original sender (A) opens a conversation with (B)
- a matrix notification is sent to (B)
- (B) adds a reply to the conversation
- a matrix notification is sent to (B)
The final matrix notification should be sent to (A) instead.
Probably the receiver of the announcement is not evaluated correctly: grouprise/features/matrix_chat/signals.py#L254