[Feature]: allow setting Monal as defaut messaging app for interactions with siri on iOS

[foss-]

Precondition

• [X] I understood that this template is only for feature requests and not for bug reports

Cross-checked related issues?

• [X] I have cross-checked this overview https://github.com/monal-im/Monal/issues/322 as well as filtered for related labels https://github.com/monal-im/Monal/labels

Describe your feature

As per https://forums.macrumors.com/threads/ios-17-how-to-choose-which-app-siri-uses-to-send-a-message.2400790/ iOS 17 will allow users to select, which app should be used to send messages.

Would be great if Monal could be used with Siri.

[tmolitor-stud-tu]

This probably needs us to implement all of this: https://blog.appnation.co/add-siri-support-to-your-ios-app-in-minutes-using-swift-86970322286

[foss-]

"in minutes" 😬

[tmolitor-stud-tu]

"in minutes" 😬

yes, and then a multi page list of things to be done follows :D