refactor: update module docstrings for clarity and consistency

backend/app/models/organization_invites.py

@@ -1,6 +1,8 @@
+"""Organization invite model for email-based tenant membership flow."""
+
 from __future__ import annotations
 
-from datetime import datetime
+from datetime import datetime  # noqa: TCH003
 from uuid import UUID, uuid4
 
 from sqlalchemy import UniqueConstraint
@@ -11,6 +13,8 @@ from app.models.base import QueryModel
 
 
 class OrganizationInvite(QueryModel, table=True):
+    """Invitation record granting prospective organization access."""
+
     __tablename__ = "organization_invites"
     __table_args__ = (UniqueConstraint("token", name="uq_org_invites_token"),)
 
@@ -21,8 +25,16 @@ class OrganizationInvite(QueryModel, table=True):
     role: str = Field(default="member", index=True)
     all_boards_read: bool = Field(default=False)
     all_boards_write: bool = Field(default=False)
-    created_by_user_id: UUID | None = Field(default=None, foreign_key="users.id", index=True)
-    accepted_by_user_id: UUID | None = Field(default=None, foreign_key="users.id", index=True)
+    created_by_user_id: UUID | None = Field(
+        default=None,
+        foreign_key="users.id",
+        index=True,
+    )
+    accepted_by_user_id: UUID | None = Field(
+        default=None,
+        foreign_key="users.id",
+        index=True,
+    )
     accepted_at: datetime | None = None
     created_at: datetime = Field(default_factory=utcnow)
     updated_at: datetime = Field(default_factory=utcnow)