Add reusable local HTTP job service for Blender add-ons

- Implement JobClient for handling HTTP requests to the JobServer.
- Create ModalJobOperatorBase for managing Blender job lifecycle.
- Introduce JobContext and JobServer for job management and state handling.
- Add ServiceConnection and ServiceController for managing service processes.
- Implement job submission, cancellation, and resource management endpoints in the server.
- Ensure proper error handling and job state updates throughout the service.

tools/validate_depth_plane_asset.py

@@ -6,7 +6,7 @@ import bpy
 
 sys.path.insert(0, str(Path(__file__).parents[1] / "src"))
 
-from snapform.image_depth import (
+from snapform.blender.depth_plane import (
     DEPTH_PLANE_MATERIAL_NODE_GROUP_NAME,
     SURFACE_MATERIAL_NODE_GROUP_NAME,
     add_depth_plane_processing,
@@ -17,7 +17,7 @@ from snapform.image_depth import (
     modifier_input_identifier,
     set_modifier_input,
 )
-from snapform.image_mesh import load_geometry_node_group
+from snapform.blender.surface import load_geometry_node_group
 
 
 def main():