model_validate ignores relationship lists

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• I already checked if it is not related to SQLModel but to Pydantic.
• I already checked if it is not related to SQLModel but to SQLAlchemy.

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Example Code

from pydantic import BaseModel
from sqlmodel import SQLModel, Relationship, Field

if __name__ == "__main__":

    # Sqlmodel classes
    class SqlChild(SQLModel, table=True):
        id: int = Field(primary_key=True, default=None)
        number: int
        parent_id: int = Field(foreign_key="sqlparent.id")

    class SqlParent(SQLModel, table=True):
        id: int = Field(primary_key=True, default=None)
        name: str
        children: list[SqlChild] = Relationship()

    # Regular pydantic classes
    class PydanticChild(BaseModel):
        id: int = Field(primary_key=True, default=None)
        number: int

    class PydanticParent(SQLModel):
        id: int = Field(primary_key=True, default=None)
        name: str
        children: list[PydanticChild]

    # Pydantic classes work as expected
    print(PydanticParent.model_validate({"name": "Hello", "children": [{"number": 4}]})) # -> id=None name='Hello' children=[PydanticChild(id=None, number=4)]
    print(PydanticParent.model_validate({"name": "Hello", "children": [PydanticChild(number=4)]})) # -> id=None name='Hello' children=[PydanticChild(id=None, number=4)]

    # Sqlmodel classes does not
    print(SqlParent.model_validate({"name": "Hello", "children": [{"number": 4}]})) # -> id=None name='Hello'
    print(SqlParent.model_validate({"name": "Hello", "children": [SqlChild(number=4)]})) # -> id=None name='Hello'

Description

Pydantic unpacks lists passed to model_validate but sqlmodel does not. If the library claims to be compatible with pydantic I'm not sure if this behaviour is correct or not

Operating System

Linux

Operating System Details

No response

SQLModel Version

0.0.24

Python Version

3.13.2

Additional Context

May be related to #1092