Extract utils code in local Swift package

[mokagio]

Xcode 14 promises build time improvements for modular apps, by "eagerly producing Swift modules". So let's get modularizing!

One way to start is by extracting utils-like code in a dedicated module or modules. That's what I prefer doing when there are no clear boundaries or the code has intricate internal dependencies. Now, I'm not saying that's the case in this codebase, but I for one haven't got a clear picture of the internal relationship between the various parts of the code, so that's where I would start.

For example, there are 32 matches for extension String when searching through Xcode: