Adding LDAP support

app/models/user.py

@@ -16,6 +16,10 @@ class User(Base):
     full_name: Mapped[str | None] = mapped_column(String(255), default=None)
     is_active: Mapped[bool] = mapped_column(Boolean, default=True)
     is_superuser: Mapped[bool] = mapped_column(Boolean, default=False)
+    # Where this account authenticates: "local" (password) or "ldap".
+    auth_provider: Mapped[str] = mapped_column(
+        String(20), default="local", server_default="local"
+    )
     created_at: Mapped[datetime] = mapped_column(
         DateTime(timezone=True), server_default=func.now()
     )