Add iOS integration testing to CI

[complexspaces]

To complete test coverage for the native platforms (WASM testing will need handled on its own), we need to add iOS testing inside of CI. This can be done via the simulator included with XCode on the GitHub actions runners. It should run the exact same tests that the Android FFI testing layer currently uses.

Past work in this area includes:

• libc's iOS testing (This may be partially defunct as-is, it does not look like its being actively used)
• security-framework's iOS test bindings (This is more involved than the libc approach, as it requires an XCode project, etc.)