macOS: Bundle fluidsynth and ghostscript (#3250)

* macOS: Build fixes for fluidsynth and ghostscript to ensure they get detected and bundled. Add required packages for build.

* macOS: Don't link against fluidsynth and only bundle if detected.

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Co-authored-by: cold-brewed <cold-brewed@users.noreply.github.com>

src/printer/CMakeLists.txt

@@ -14,3 +14,10 @@
 #
 
 add_library(print OBJECT png.c prt_cpmap.c prt_escp.c prt_text.c prt_ps.c)
+
+if(APPLE)
+    find_library(GHOSTSCRIPT_LIB gs)
+    if (NOT GHOSTSCRIPT_LIB)
+        message(WARNING "Could not find ghostscript. The library will not be bundled and any related features will not work.")
+    endif()
+endif ()