feat: import F95 screenshot galleries with AVIF support

backend/migrations/versions/0006_game_gallery.py

@@ -0,0 +1,16 @@
+"""Locally stored game screenshots."""
+import sqlalchemy as sa
+from alembic import op
+
+revision = "0006"
+down_revision = "0005"
+branch_labels = depends_on = None
+
+
+def upgrade():
+    op.add_column("games", sa.Column("gallery_hashes", sa.ARRAY(sa.String(80)),
+                                    nullable=False, server_default="{}"))
+
+
+def downgrade():
+    op.drop_column("games", "gallery_hashes")