Refactor image handling and update foreground processing

- Changed the logic in `remove_background_faces` to keep only faces with all foreground vertices.
- Updated background job to save foreground images with a new naming convention (`color.0001.png`).
- Replaced `copy_frames` with `copy_color_images` in various jobs to ensure consistent image naming.
- Introduced a new function `copy_color_images` to handle the copying of images with a specific naming format.
- Updated the BEN2 model to save output images with a new prefix for better clarity.
- Modified tests to reflect changes in image naming and processing logic.
- Added a new shadeless node group for improved material handling in geometry nodes.
- Enhanced validation scripts to check for new image naming conventions and ensure proper functionality.

tests/test_addon.py

@@ -686,7 +686,7 @@ class AddonTest(unittest.TestCase):
         operator.source_object_name = "Reference"
         operator.remove_background = False
         operator.delete_source = True
-        operator.unshaded = False
+        operator.shadeless = False
         result = object()
         context = object()
 
@@ -701,7 +701,7 @@ class AddonTest(unittest.TestCase):
             source_object_name="Reference",
             remove_background=False,
             delete_source=True,
-            unshaded=False,
+            shadeless=False,
         )
 
     def test_entry_operator_dispatches_plain_properties(self):
@@ -709,7 +709,7 @@ class AddonTest(unittest.TestCase):
         operator.model = "MOGE2_VITS_NORMAL"
         operator.resolution_level = 7
         operator.keep_original = False
-        operator.unshaded = True
+        operator.shadeless = True
         operator.remove_background = False
         source_object = SimpleNamespace(
             name="Reference",