EX Expected UTDs: use a different message for expected UTDs (parity with web)

[BillCarsonFr]

Parity with web

EX only says Waiting for this message

Historical expected UTDs:

See https://github.com/matrix-org/matrix-react-sdk/pull/12391

Web displays different messages for historical expected UTDs, with some call to action if applicable:

• Historical Messages are not availble on this device => When Key storage is not configured
• You need to verify this device to access historical messages => When there is backup but the decryption key is missing?

Pre join UTD:

Web says You don't have access to this message

[andybalaam]

This needs to build on top of the types introduced in https://github.com/element-hq/element-meta/issues/2581