Support matrix URI scheme

[Apple allows](https://developer.apple.com/documentation/xcode/defining-a-custom-url-scheme-for-your-app) apps to specify a custom URI handler, with the merge of the [Matrix URI](https://github.com/matrix-org/matrix-doc/pull/2312) proposal, this means that the URI can be referenced from links, redirects, and other formats.