Call Objc Function from Swift within a SwiftPM-Framework

I use Xcode 15.3.
Short story:
Calling 'Call_MBLog' from within a framework doesn't work (see below).
Calling 'Call_MBLog' from the main-app works. E.g.:

//
// ContentView.swift
//

import Check_iOSDebugFrameWork2407Pkg

import SwiftUI

struct ContentView: View {
	var body: some View {
		VStack {
			Image(systemName: "globe")
				.imageScale(.large)
				.foregroundStyle(.tint)
			Text("Hello, world!")
			
			let InputNumer: Int32	= 42
			let ResultNumber		= Call_MBLog (InputNumer)
			Text ("ResultNumber: \(ResultNumber)")
		}
		.padding()
	}
}
      //  
      // SwiftFiles/CheckGlobalFunctions.swift
      //  
    
      import Foundation
    
      public func MBLog(_ aString: String) {
        print("MBLog (CheckGlobalFunctions.swift): aString: [\(aString)]")
        let InputNumer: Int32                       = 42
      //    var ResultNumber                            = Call_MBLog (InputNumer)   // Cannot find 'Call_MBLog' in scope
      } 

My Framework-Structure is like this:

|_Check_iOSDebugFrameWork2407Pkg.h
  #--------------------------------------------------
  //
  // Check_iOSDebugFrameWork2407Pkg.h
  //
  
  #import <Foundation/Foundation.h>
  
  //! Project version number for Check_iOSDebugFrameWork2407Pkg.
  FOUNDATION_EXPORT double Check_iOSDebugFrameWork2407PkgVersionNumber;
  
  //! Project version string for Check_iOSDebugFrameWork2407Pkg.
  FOUNDATION_EXPORT const unsigned char Check_iOSDebugFrameWork2407PkgVersionString[];
  
  // Import all the public headers of your framework
  #import <Check_iOSDebugFrameWork2407Pkg/RunTimeInfoFw.h>
  
  // Swift module will be automatically imported
  #--------------------------------------------------

|_Package.swift
  #--------------------------------------------------
  // swift-tools-version:5.3
  
  import PackageDescription
  
  let package = Package(
  	name: "Check_iOSDebugFrameWork2407Pkg",
  	platforms: [.iOS(.v12)],
  	products: [
  		.library(
  			name: "Check_iOSDebugFrameWork2407Pkg",
  			targets: ["Check_iOSDebugFrameWork2407Pkg"]),
  	],
  	dependencies: [],
  	targets: [
  		.target(
  			name: "Check_iOSDebugFrameWork2407Pkg",
  			dependencies: [
  				"Check_iOSDebugFrameWork2407ObjC",
  				"Check_iOSDebugFrameWork2407Swift"
  			],
  			path: "Sources/Check_iOSDebugFrameWork2407Pkg",
  			sources: ["Dummy.swift"]  // We'll create this file
  		),
  		.target(
  			name: "Check_iOSDebugFrameWork2407ObjC",
  			path: "Sources/ObjCFiles"
  		),
  		.target(
  			name: "Check_iOSDebugFrameWork2407Swift",
  			path: "Sources/SwiftFiles"
  		),
  //		.testTarget(
  //			name: "Check_iOSDebugFrameWork2407PkgTests",
  //			dependencies: ["Check_iOSDebugFrameWork2407Pkg"]),
  	],
  	swiftLanguageVersions: [.v4_2]
  )
  #--------------------------------------------------

|_Sources
|||_Check_iOSDebugFrameWork2407Pkg
|||||_Check_iOSDebugFrameWork2407Pkg.h
      #--------------------------------------------------
      //
      // Check_iOSDebugFrameWork2407Pkg.h
      //
      
      #import <Foundation/Foundation.h>
      
      //! Project version number for Check_iOSDebugFrameWork2407Pkg.
      FOUNDATION_EXPORT double Check_iOSDebugFrameWork2407PkgVersionNumber;
      
      //! Project version string for Check_iOSDebugFrameWork2407Pkg.
      FOUNDATION_EXPORT const unsigned char Check_iOSDebugFrameWork2407PkgVersionString[];
      
      // Import all the public headers of your framework
      #import <Check_iOSDebugFrameWork2407Pkg/RunTimeInfoFw.h>
      
      // Swift module will be automatically imported
      #--------------------------------------------------

|||||_Dummy.swift
      #--------------------------------------------------
      //
      // Check_iOSDebugFrameWork2407Pkg/Dummy.swift
      //
      
      // This file is needed to satisfy SPM requirements
      
      @_exported import Check_iOSDebugFrameWork2407ObjC
      @_exported import Check_iOSDebugFrameWork2407Swift
      #--------------------------------------------------

|||_ObjCFiles
|||||_CheckMBLog.m
      #--------------------------------------------------
      //
      // ObjCFiles/CheckMBLog.m
      //
      
      #import <Foundation/Foundation.h>
      #import "CheckMBLog.h"
      
      int Call_MBLog (int Number) {
      	return Number * 2;
      }
      #--------------------------------------------------

|||||_include
|||||||_CheckMBLog.h
        #--------------------------------------------------
        //
        // Sources/ObjCFiles/include/CheckMBLog.h
        //
        
        #ifndef CheckMBLog_h
        #define CheckMBLog_h
        
        // Fix "Unknown type name 'bool'"
        #import <Foundation/Foundation.h>
        
        int Call_MBLog (int Number);
        
        //NS_ASSUME_NONNULL_BEGIN
        //
        //FOUNDATION_EXPORT int32_t Call_MBLog(int32_t inputNumber);
        //
        //NS_ASSUME_NONNULL_END
        
        #endif /* CheckMBLog_h */
        #--------------------------------------------------

|||||||_Check_iOSDebugFrameWork2407Pkg.h
        #--------------------------------------------------
        //
        // Sources/ObjCFiles/include/Check_iOSDebugFrameWork2407Pkg.h
        //
        
        #import <Foundation/Foundation.h>
        
        //! Project version number for Check_iOSDebugFrameWork2407Pkg.
        FOUNDATION_EXPORT double Check_iOSDebugFrameWork2407PkgVersionNumber;
        
        //! Project version string for Check_iOSDebugFrameWork2407Pkg.
        FOUNDATION_EXPORT const unsigned char Check_iOSDebugFrameWork2407PkgVersionString[];
        
        // Import all public Objective-C headers
        #import "CheckMBLog.h"
        //#import <Check_iOSDebugFrameWork2407Pkg/CheckMBLog.h>
        #--------------------------------------------------

|||_SwiftFiles
|||||_CheckGlobalFunctions.swift
      #--------------------------------------------------
      //
      // SwiftFiles/CheckGlobalFunctions.swift
      //
      
      import Foundation
      
      public func MBLog(_ aString: String) {
      	print("MBLog (CheckGlobalFunctions.swift): aString: [\(aString)]")
      	let InputNumer: Int32						= 42
      //	var ResultNumber							= Call_MBLog (InputNumer)	// Cannot find 'Call_MBLog' in scope
      }
      
      public func getCheckResult() -> String {
      	return "Any Result 1"
      }
      #--------------------------------------------------

|||||_Check_iOSDebugFrameWork2407Pkg-Bridging-Header.h
      #--------------------------------------------------
      //
      // SwiftFiles/Check_iOSDebugFrameWork2407Pkg-Bridging-Header.h
      //
      
      #import "CheckMBLog.h"
      #--------------------------------------------------

Thanks for any hint.

Markus