Stamps a SwiftPM manifest onto the scaffold so the package can be
consumed by the CxLLM-SDK umbrella and downstream apps. The seed
source exposes a versioned namespace placeholder; real implementation
lands in subsequent phases.
The directory was already named CxLLM-LIB but the .xcodeproj, target,
product name, and built dylib used the abbreviated 'CxLLM-LB' form.
Rename the project bundle, all internal pbxproj references, and the
Aggregate workspace pointer so naming is consistent everywhere.