Update file dialog source selection in z3ed CMake configuration

- Modified the FILE_DIALOG_SRC variable to include both platform-independent and macOS-specific source files.
- This change enhances clarity by explicitly indicating the purpose of each source file in the CMake configuration.

src/cli/z3ed.cmake

@@ -13,7 +13,10 @@ endif()
 
 # Platform-specific file dialog sources
 if(APPLE)
-  set(FILE_DIALOG_SRC app/core/platform/file_dialog.mm)
+  set(FILE_DIALOG_SRC 
+    app/core/platform/file_dialog.cc   # Utility functions (all platforms)
+    app/core/platform/file_dialog.mm   # macOS-specific dialogs
+  )
 else()
   set(FILE_DIALOG_SRC app/core/platform/file_dialog.cc)
 endif()