feat: Add MoGe-2 surface generation and export functionality

- Introduced new enum items for depth plane and surface models with caching.
- Added MOGE2_MESH_JOB to operators for converting images to surfaces.
- Implemented surface mesh building and exporting in RunJob operator.
- Enhanced UI to include export format options for MoGe-2.
- Created validation tools for MoGe-2 surface assets and depth planes.
- Updated geometry nodes to support new surface generation features.
- Refactored existing tests to accommodate new functionality and ensure stability.

tools/validate_depth_plane_asset.py

@@ -20,6 +20,13 @@ from snapform.image_mesh import load_geometry_node_group
 def main():
     bpy.ops.wm.read_factory_settings(use_empty=True)
     group = load_depth_plane_node_group()
+    geometry_textures = [
+        node
+        for node in group.nodes
+        if node.bl_idname == "GeometryNodeImageTexture"
+    ]
+    assert geometry_textures
+    assert all(node.extension == "EXTEND" for node in geometry_textures)
     background_depth = next(
         item
         for item in group.interface.items_tree
@@ -212,6 +219,11 @@ def main():
         node.bl_idname in forbidden_outer_nodes
         for node in material.node_tree.nodes
     )
+    assert all(
+        node.extension == "EXTEND"
+        for node in material.node_tree.nodes
+        if node.bl_idname == "ShaderNodeTexImage"
+    )
     surface_material = create_material("Surface", foreground, 1.0)
     surface_group = bpy.data.node_groups[SURFACE_MATERIAL_NODE_GROUP_NAME]
     surface_group_nodes = [
@@ -251,6 +263,11 @@ def main():
         node.bl_idname in forbidden_outer_nodes
         for node in surface_material.node_tree.nodes
     )
+    assert all(
+        node.extension == "EXTEND"
+        for node in surface_material.node_tree.nodes
+        if node.bl_idname == "ShaderNodeTexImage"
+    )
     modifier = add_depth_plane_processing(
         obj,
         depth,