Prepare 0.4.14 release

[simolus3]

This bumps the version number to 0.4.14. The only change since the last release is that the static library for watchOS is now built correctly (#177).

I've also added a document listing how the core extension is integrated into our different SDKs. Hopefully, this helps to understand the build setup and why we're building different libraries. I'm also interested in potentially simplifying that a bit. This PR doesn't change anything, but it seems like:

1. We can drop the SwiftPM XCFramework published through the other git repository (it's currently recommended for Kotlin users but we're migrating away from that, and the Swift SDK could download the xcframework from releases directly).
2. We could drop the dynamic/side-module WASM builds since they aren't used (but my understanding is we might want to bring wa-sqlite into a state where they could be used in the future).