add LanceModel to docs (#386)

Co-authored-by: Chang She <chang@lancedb.com>

docs/src/python/pydantic.md

@@ -3,7 +3,6 @@
 [Pydantic](https://docs.pydantic.dev/latest/) is a data validation library in Python.
 LanceDB integrates with Pydantic for schema inference, data ingestion, and query result casting.
 
-
 ## Schema
 
 LanceDB supports to create Apache Arrow Schema from a

docs/src/python/python.md

@@ -56,4 +56,4 @@ pip install lancedb
 
 ::: lancedb.pydantic.vector
 
-
+::: lancedb.pydantic.LanceModel

python/lancedb/pydantic.py

@@ -275,10 +275,16 @@ class LanceModel(pydantic.BaseModel):
 
     @classmethod
     def to_arrow_schema(cls):
+        """
+        Get the Arrow Schema for this model.
+        """
         return pydantic_to_schema(cls)
 
     @classmethod
     def field_names(cls) -> List[str]:
+        """
+        Get the field names of this model.
+        """
         if PYDANTIC_VERSION.major < 2:
             return list(cls.__fields__.keys())
         return list(cls.model_fields.keys())