fix(delete-modal): close modal after successful delete

The success path of handleConfirm() never reset the isSubmitting flag,
so hide()'s early-return guard (line 209: 'if (isSubmitting) return')
kept the modal visible after a successful delete — leaving the user
looking at a stuck 'Deleting...' dialog while the card had already been
removed by the WebSocket SERIES_DELETED event.

Reset isSubmitting and the confirm button text before calling hide(),
and capture currentKey into a local before hide() nulls it so the
follow-up removeSeries() call receives the right key.

src/server/web/static/js/index/delete-modal.js

@@ -300,6 +300,9 @@ AniWorld.DeleteModal = (function() {
             var result = await response.json();
             console.info('[DeleteModal] Delete succeeded:', result);
 
+            // Capture key before hide() nulls currentKey
+            var deletedKey = currentKey;
+
             // Show success message based on what was deleted
             var msgParts = [];
             if (result.deleted_from_database) msgParts.push('removed from database');
@@ -311,11 +314,17 @@ AniWorld.DeleteModal = (function() {
                 : 'Delete completed.';
 
             AniWorld.UI.showToast(successMsg, result.success ? 'success' : 'warning');
+
+            // Close modal and reset submission state together — isSubmitting must
+            // be cleared before hide(), otherwise hide() bails out (early return
+            // on the !isSubmitting guard) and the modal stays visible.
+            isSubmitting = false;
+            if (confirmBtn) confirmBtn.textContent = 'Delete';
             hide();
 
             // Remove the card from the grid directly
             if (AniWorld.SeriesManager && AniWorld.SeriesManager.removeSeries) {
-                AniWorld.SeriesManager.removeSeries(currentKey);
+                AniWorld.SeriesManager.removeSeries(deletedKey);
             }
 
         } catch (err) {