spmBridgeMmForwarder function
A nitrogen init .mm forwarder for the SPM C++ target.
The 4-level relative path is fixed for the nested SPM layout:
{platform}/{plugin}/Sources/{Plugin}Cpp/ → lib/src/generated/cpp/
Implementation
String spmBridgeMmForwarder(String pluginName) =>
'// Generated by nitrogen init — do not edit.\n'
'// Updated with resolved paths by nitrogen link.\n'
'#import <Foundation/Foundation.h>\n'
'#include "../../../../lib/src/generated/cpp/$pluginName.bridge.g.cpp"\n';