Improve API controllers: case-insensitive search, scoped queries, cleanup

src/controllers/importController.js

@@ -122,6 +122,7 @@ async function importCardsInternal() {
             await conn.execute(`
               INSERT INTO card_images (card_id, image_url)
               VALUES (?, ?)
+              ON DUPLICATE KEY UPDATE image_url = VALUES(image_url)
             `, [card.id, img.image_url]);
             addedImages++;
           }
@@ -136,7 +137,6 @@ async function importCardsInternal() {
       conn.release();
     }
 
-    batch.length = 0;
   }
 
   const durationSeconds = ((Date.now() - startTime) / 1000).toFixed(2);