Permalinks to messages should be pillified

[giomfo]

Part of element-hq/element-meta#1030

We decided to not pillify permalinks to message when they have been sent formatted (markdown).
The following changes will be applied on permalinks to message only if they are not sent formatted:

Permalinks to a message in the same room

• When a user has shared a permalink to a message in the same room,

it should show like this:
If we failed to retrieve the event or the sender details, just show "Message" as a pill with the link icon

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Permalinks to a message in a different room

• When a user has shared a permalink to a message in another room

it should show like this (with the avatar and room name):
If these are not available, apply the same logic as above (the pill should show the default room icon and "Room")

Note2: the avatar and the room name may be retrieved by using the Room summary API

[giomfo]

Done v1.10.6

Note: the same fallback pill has been used for both cases (permalink to a message in a different room and permalink to a message in the same room).