[TargetIntegrator] Ensure the embed frameworks script is added when migrating and integrating via static libs

[Installer] Fix source locking/unlocking

[Generator] Fix missing `$(inherited)` in xcconfig build settings

- Add missing `$(inherited)` values for the build settings `LIBRARY_SEARCH_PATHS` and `HEADER_SEARCH_PATHS` in generated xcconfig files.
- Update tests to explicitly check for these `$(inherited)` values.

Fixes #3908

The `HEADER_SEARCH_PATHS` will no longer be constructed recursively.

Embed frameworks into app and watch extensions.

[Validator] Add private mode