Add updated_at and created_at to Playlist model

Introduces created_at and updated_at fields to the Playlist model for tracking creation and modification times. Refactors room user removal logic to handle owner transfer and participant count updates more robustly. Updates room query logic for more accurate filtering by category and status. Adds migration stubs for updated_at column in room playlists.

migrations/versions/20c6df84813f_add_updated_at_column_to_room_playlists.py

@@ -0,0 +1,26 @@
+"""add_updated_at_column_to_room_playlists
+
+Revision ID: 20c6df84813f
+Revises: 57bacf936413
+Create Date: 2025-08-24 00:08:14.704724
+
+"""
+from __future__ import annotations
+
+from collections.abc import Sequence
+
+# revision identifiers, used by Alembic.
+revision: str = "20c6df84813f"
+down_revision: str | Sequence[str] | None = "57bacf936413"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    pass
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    pass

migrations/versions/7576ca1e056d_add_updated_at_column_to_room_playlists.py

@@ -0,0 +1,26 @@
+"""add_updated_at_column_to_room_playlists
+
+Revision ID: 7576ca1e056d
+Revises: 20c6df84813f
+Create Date: 2025-08-24 00:08:42.419252
+
+"""
+from __future__ import annotations
+
+from collections.abc import Sequence
+
+# revision identifiers, used by Alembic.
+revision: str = "7576ca1e056d"
+down_revision: str | Sequence[str] | None = "20c6df84813f"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    pass
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    pass

migrations/versions/8d2af11343b9_add_updated_at_column_to_room_playlists.py

@@ -0,0 +1,26 @@
+"""add_updated_at_column_to_room_playlists
+
+Revision ID: 8d2af11343b9
+Revises: 7576ca1e056d
+Create Date: 2025-08-24 00:11:05.064099
+
+"""
+from __future__ import annotations
+
+from collections.abc import Sequence
+
+# revision identifiers, used by Alembic.
+revision: str = "8d2af11343b9"
+down_revision: str | Sequence[str] | None = "7576ca1e056d"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    pass
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    pass