(fix) update freeU config to be compatible with custom nodes (#5050)

## What type of PR is this? (check all applicable)

- [ ] Refactor
- [ ] Feature
- [X] Bug Fix
- [ ] Optimization
- [ ] Documentation Update
- [ ] Community Node Submission


## Have you discussed this change with the InvokeAI team?
- [X] Yes: @psychedelicious told me to do this :) 
- [ ] No, because:

      
## Have you updated all relevant documentation?
- [ ] Yes
- [ ] No


## Description


## Related Tickets & Documents

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- Related Issue #
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## QA Instructions, Screenshots, Recordings

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## Added/updated tests?

- [ ] Yes
- [ ] No : _please replace this line with details on why tests
      have not been included_

## [optional] Are there any post deployment tasks we need to perform?

invokeai/app/invocations/model.py

@@ -3,8 +3,6 @@ from typing import List, Optional
 
 from pydantic import BaseModel, ConfigDict, Field
 
-from invokeai.app.invocations.shared import FreeUConfig
-
 from ...backend.model_management import BaseModelType, ModelType, SubModelType
 from .baseinvocation import (
     BaseInvocation,
@@ -19,6 +17,22 @@ from .baseinvocation import (
     invocation_output,
 )
 
+# TODO: Permanent fix for this
+# from invokeai.app.invocations.shared import FreeUConfig
+
+
+class FreeUConfig(BaseModel):
+    """
+    Configuration for the FreeU hyperparameters.
+    - https://huggingface.co/docs/diffusers/main/en/using-diffusers/freeu
+    - https://github.com/ChenyangSi/FreeU
+    """
+
+    s1: float = Field(ge=-1, le=3, description=FieldDescriptions.freeu_s1)
+    s2: float = Field(ge=-1, le=3, description=FieldDescriptions.freeu_s2)
+    b1: float = Field(ge=-1, le=3, description=FieldDescriptions.freeu_b1)
+    b2: float = Field(ge=-1, le=3, description=FieldDescriptions.freeu_b2)
+
 
 class ModelInfo(BaseModel):
     model_name: str = Field(description="Info to load submodel")