CMake: build StreamWriter only into JFJochStreamWriter

StreamWriter.cpp was compiled into both JFJochWriter and JFJochStreamWriter,
so JFJochWriter still transitively pulled in image_puller headers via
StreamWriter.h. Compile it only into JFJochStreamWriter (which already
links JFJochImagePuller); targets needing the streaming writer (jfjoch_writer,
jfjoch_test) link that lib, while JFJochWriter consumers (viewer, tools,
ImagePusher) no longer drag in the puller. Also drop a stray duplicate
HDF5DataFile source listing.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

writer/CMakeLists.txt

@@ -11,8 +11,6 @@ ADD_LIBRARY(JFJochWriter STATIC
         HDF5DataFile.h  HDF5DataFile.cpp
         HDF5NXmx.cpp      HDF5NXmx.h
         FileWriter.cpp FileWriter.h
-        StreamWriter.cpp StreamWriter.h
-        HDF5DataFile.h  HDF5DataFile.cpp
         HDF5DataFilePlugin.cpp
         HDF5DataFilePlugin.h
         HDF5DataFilePluginROI.cpp