Remove obsolete implementation and simplify project structure

src/anyimage/server/outputs/__init__.py

@@ -0,0 +1,10 @@
+from .depth import write_da3_depth, write_moge_depth
+from .surface import write_normal_texture, write_surface_archive
+
+
+__all__ = (
+    "write_da3_depth",
+    "write_moge_depth",
+    "write_normal_texture",
+    "write_surface_archive",
+)