[Room History] add specific encryption tiles in the room history

### Your use case

The Element-Web client displays a tile at the beginning of the unencrypted room in order to highlight the encryption is disabled

Element-web displays another tile for the encrypted rooms:

I suggest here displaying the same tiles in the room history in Element-ios

Note: in Element-web the tile is not displayed in unencrypted room if the join_rule is public (the room is accessible by link)

Start by locating the Element-iOS room-history rendering and compare its beginning-of-history behavior with the Element-Web examples described in the issue. The work is done when encrypted rooms show the corresponding encryption tile and unencrypted rooms show the disabled-encryption tile, except when the join rule is public.

Written by the indexing model from the issue text.