Migrate legacy strings file to catalog

[ioanmo226]

XCode 15 introduced new string catalogs feature which gives us flexible control over localization.

https://developer.apple.com/documentation/Xcode/localizing-and-varying-text-with-a-string-catalog

[ioanmo226]

@sosnovsky What do you think?

[sosnovsky]

Looks like localising apps will be much easier with this string catalog functionality, and it's great that it'll be supported in older iOS versions too. But we should migrate to it only when final version of Xcode 15 will be released, as App Store doesn't allow to upload apps from beta versions of Xcode. I'll move it to Later milestone for now

[tomholub]

plus, I'd like to not do too much maintenance on ios right now, except for high impact lower effort items. It would be good to focus on usability