Only offer to verify if a cross-signed device is available

[uhoreg]

Fixes #4190

Confirming your identity by verifying against another device only works if the other device that you're verifying against has been cross-signed. Currently, when you try to confirm your identity, it will prompt you to verify against another device if you have any other device (with device keys) available. This PR uses a new function in the Rust SDK (introduced in matrix-org/matrix-rust-sdk#5699) to detect whether there are other devices that have been cross-signed that the user can verify against.

(The equivalent Element X Android PR was element-hq/element-x-android#5433)

Pull Request Checklist

• I read the contributing guide.
• Pull request contains a changelog label.

UI changes have been tested with:

• iPhone and iPad simulators in portrait and landscape orientations.
• Dark mode enabled and disabled.
• Various sizes of dynamic type.
• Voiceover enabled.

[uhoreg]

"Unit Tests" failure seems to be swiftformat complaining about a file that I didn't change, and not actually running the unit tests.

[pixlwave]

"Unit Tests" failure seems to be swiftformat complaining about a file that I didn't change, and not actually running the unit tests.

This should be fixed with a rebase on develop 👍

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[uhoreg]

Unit Tests are now running, kind of. It looks like some tests run, and pass. But then it says [13:54:38]: ▸ Testing started in the logs, and then sits there for several hours, with nothing else showing in the logs, until the task finally gets killed.

[stefanceriu]

sits there for several hours

Don't worry about that, we've been having issues with CI runners ever since moving to os26. You need to cancel, rerun and then hope for the best (which is failing horribly in this situation).