Implement BiRefNet and HAT Sharper models with background removal capabilities

- Added validation documentation for AI model tiers.
- Introduced `background.py` for background removal logic, including inference functions for alpha and foreground extraction.
- Created `onnx_birefnet.py` to handle BiRefNet model sessions and alpha inference.
- Developed tests for background models, ensuring proper dispatch and session reuse.
- Added tests for BiRefNet ONNX model to validate alpha output and error handling for invalid values.
- Implemented model export scripts for BiRefNet and HAT Sharper, ensuring proper weight compression and licensing.
- Created `deform_sampling.py` for deformable convolution operations used in BiRefNet.
- Added utility functions for compressing ONNX weights without altering graph arithmetic.
- Introduced a reference plane node for depth field adjustments in geometry processing.

tests/anyimage/operators/test_panorama_conversion.py

@@ -43,11 +43,12 @@ def test_entry_submits_current_alpha_preferences_and_cleans_cancelled_input(sour
         return {"CANCELLED"}
     monkeypatch.setattr(operators, "invoke_ai_setup_if_needed", lambda _operator: None)
     monkeypatch.setattr(operators, "addon_preferences", lambda _: SimpleNamespace(geometry_model="MOGE2_VITB", geometry_resolution_level=2))
+    monkeypatch.setattr(operators, "configured_geometry_model", lambda _: "MOGE2_VITB_NORMAL")
     monkeypatch.setattr(operators, "configured_max_ai_input_size", lambda _: 1024)
     monkeypatch.setattr(operators, "bpy", SimpleNamespace(ops=SimpleNamespace(anyimage=SimpleNamespace(generate_panorama=submit))))
     operator = SimpleNamespace(mesh_detail=4, report=Mock())
     assert operators.ConvertToPanorama.execute(operator, bpy.context) == {"CANCELLED"}
-    assert submitted["model"] == "MOGE2_VITB" and submitted["resolution_level"] == 2
+    assert submitted["model"] == "MOGE2_VITB_NORMAL" and submitted["resolution_level"] == 2
     assert submitted["max_input_size"] == 1024 and submitted["mesh_detail"] == 4
     assert submitted["color_path"] == submitted["input_path"]
     from pathlib import Path