Update seller store experience

packages/database/migrations/017_collection_video_candidates.sql

@@ -0,0 +1,10 @@
+SET search_path TO atlas, public;
+
+CREATE TYPE collection_media_type AS ENUM ('image', 'video');
+
+ALTER TABLE collection_asset_transfers
+    ADD COLUMN media_type collection_media_type NOT NULL DEFAULT 'image',
+    ADD COLUMN poster_url TEXT;
+
+CREATE INDEX collection_asset_transfers_media_status_idx
+    ON collection_asset_transfers (workspace_id, media_type, status, created_at);