Pydantic recommends not to use model_ prefix for model fields

[rapsealk]

What Operating System(s) are you seeing this problem on?

Linux (x86-64)

Backend.AI version

b835aff

Describe the bug

During the manager bootstrapping process, the following warning logs were identified:

/Users/rapsealk/Desktop/git/backend.ai-dev2/dist/export/python/virtualenvs/python-default/3.11.6/lib/python3.11/site-packages/pydantic/_internal/_fields.py:128: UserWarning: Field "model_version" conflicts with the protected namespace "model_".

You may resolve this warning by setting `model_config['protected_namespaces'] = ()`.
warnings.warn(
/Users/rapsealk/Desktop/git/backend.ai-dev2/dist/export/python/virtualenvs/python-default/3.11.6/lib/python3.11/site-packages/pydantic/_internal/_fields.py:128: UserWarning: Field "model_mount_destination" conflicts with the protected namespace "model_".

You may resolve this warning by setting `model_config['protected_namespaces'] = ()`.

backend.ai/src/ai/backend/manager/api/service.py

Lines 235 to 246 in b835aff

	model_version: int = Field(
	validation_alias=AliasChoices("model_version", "modelVersion"),
	description="Unused; Reserved for future works",
	default=1,
	)
	model_mount_destination: str = Field(
	validation_alias=AliasChoices("model_mount_destination", "modelMountDestination"),
	default="/models",
	description=(
	"Mount destination for the model VFolder will be mounted inside the inference session"
	),
	)

As per Pydantic documentation, the protected_namespaces: tuple[str, ...] configuration is designed to prevent namespace collision or overwriting preexisting attributes. While this warning may not impact the running process itself yet, it is advisable to take action to suppress such warnings.

Please refer to Configuration - Pydantic for more comprehensive details.

To Reproduce

Execute the following command:

$ backend.ai mgr start-server --debug

Expected Behavior

No warnings.

Anything else?

No response