refactor: update module docstrings for clarity and consistency

backend/app/schemas/users.py

@@ -1,11 +1,15 @@
+"""User API schemas for create, update, and read operations."""
+
 from __future__ import annotations
 
-from uuid import UUID
+from uuid import UUID  # noqa: TCH003
 
 from sqlmodel import SQLModel
 
 
 class UserBase(SQLModel):
+    """Common user profile fields shared across user payload schemas."""
+
     clerk_user_id: str
     email: str | None = None
     name: str | None = None
@@ -17,10 +21,12 @@ class UserBase(SQLModel):
 
 
 class UserCreate(UserBase):
-    pass
+    """Payload used to create a user record."""
 
 
 class UserUpdate(SQLModel):
+    """Payload for partial user profile updates."""
+
     name: str | None = None
     preferred_name: str | None = None
     pronouns: str | None = None
@@ -30,5 +36,7 @@ class UserUpdate(SQLModel):
 
 
 class UserRead(UserBase):
+    """Full user payload returned by API responses."""
+
     id: UUID
     is_super_admin: bool