refactor(nodes): model identifiers

- All models are identified by a key and optionally a submodel type via new model `ModelField`. Previously, a few model types had their own class, but not all of them. This inconsistency just added complexity without any benefit.
- Update all invocation to use the new format.
- In the node API, models are loaded by key or an instance of `ModelField` as a convenience.
- Add an enriched model schema for metadata. It includes key, hash, name, base and type.

invokeai/invocation_api/__init__.py

@@ -35,17 +35,13 @@ from invokeai.app.invocations.metadata import MetadataItemField, MetadataItemOut
 from invokeai.app.invocations.model import (
     ClipField,
     CLIPOutput,
-    LoraInfo,
     LoraLoaderOutput,
-    LoRAModelField,
-    MainModelField,
-    ModelInfo,
+    ModelField,
     ModelLoaderOutput,
     SDXLLoraLoaderOutput,
     UNetField,
     UNetOutput,
     VaeField,
-    VAEModelField,
     VAEOutput,
 )
 from invokeai.app.invocations.primitives import (
@@ -73,8 +69,8 @@ from invokeai.app.services.image_records.image_records_common import ImageCatego
 from invokeai.app.services.shared.invocation_context import InvocationContext
 from invokeai.app.services.workflow_records.workflow_records_common import WorkflowWithoutID
 from invokeai.app.util.misc import SEED_MAX, get_random_seed
-from invokeai.backend.model_management.model_manager import LoadedModelInfo
-from invokeai.backend.model_management.models.base import BaseModelType, ModelType, SubModelType
+from invokeai.backend.model_manager.config import BaseModelType, ModelType, SubModelType
+from invokeai.backend.model_manager.load.load_base import LoadedModel
 from invokeai.backend.stable_diffusion.diffusers_pipeline import PipelineIntermediateState
 from invokeai.backend.stable_diffusion.diffusion.conditioning_data import (
     BasicConditioningInfo,
@@ -118,14 +114,10 @@ __all__ = [
     "MetadataItemOutput",
     "MetadataOutput",
     # invokeai.app.invocations.model
-    "ModelInfo",
-    "LoraInfo",
+    "ModelField",
     "UNetField",
     "ClipField",
     "VaeField",
-    "MainModelField",
-    "LoRAModelField",
-    "VAEModelField",
     "UNetOutput",
     "VAEOutput",
     "CLIPOutput",
@@ -166,7 +158,7 @@ __all__ = [
     # invokeai.app.services.config.config_default
     "InvokeAIAppConfig",
     # invokeai.backend.model_management.model_manager
-    "LoadedModelInfo",
+    "LoadedModel",
     # invokeai.backend.model_management.models.base
     "BaseModelType",
     "ModelType",