feat(ui): add Clear All button to download queue header (#96)

CHANGELOG.md

@@ -4,6 +4,10 @@
 
 ### Added
 
+- **Clear All Queue Button**: Added "Clear All" button next to Pause/Resume in the Downloading section header ([#96](https://github.com/zarzet/SpotiFLAC-Mobile/issues/96))
+  - Quickly cancel all queued downloads with one tap
+  - Confirmation dialog prevents accidental clears
+  - Useful when downloading large playlists
 - **IDHS Fallback**: Added I Don't Have Spotify (IDHS) as fallback link resolver when SongLink fails
   - Automatically tries IDHS when SongLink returns errors or rate limits
   - Supports both Spotify→other platforms and Deezer→other platforms lookups

lib/screens/queue_tab.dart

@@ -793,6 +793,8 @@ final queueItems = ref.watch(downloadQueueProvider.select((s) => s.items));
                         ),
                         const Spacer(),
                         _buildPauseResumeButton(context, ref, colorScheme),
+                        const SizedBox(width: 4),
+                        _buildClearAllButton(context, ref, colorScheme),
                       ],
                     ),
                   ),
@@ -1177,6 +1179,53 @@ if (queueItems.isEmpty &&
     );
   }
 
+  Widget _buildClearAllButton(
+    BuildContext context,
+    WidgetRef ref,
+    ColorScheme colorScheme,
+  ) {
+    return TextButton.icon(
+      onPressed: () => _showClearAllDialog(context, ref, colorScheme),
+      icon: const Icon(Icons.clear_all, size: 18),
+      label: Text(context.l10n.queueClearAll),
+      style: TextButton.styleFrom(
+        visualDensity: VisualDensity.compact,
+        foregroundColor: colorScheme.error,
+      ),
+    );
+  }
+
+  Future<void> _showClearAllDialog(
+    BuildContext context,
+    WidgetRef ref,
+    ColorScheme colorScheme,
+  ) async {
+    final confirmed = await showDialog<bool>(
+      context: context,
+      builder: (ctx) => AlertDialog(
+        title: Text(context.l10n.queueClearAll),
+        content: Text(context.l10n.queueClearAllMessage),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(ctx, false),
+            child: Text(context.l10n.dialogCancel),
+          ),
+          FilledButton(
+            onPressed: () => Navigator.pop(ctx, true),
+            style: FilledButton.styleFrom(
+              backgroundColor: colorScheme.error,
+            ),
+            child: Text(context.l10n.dialogClear),
+          ),
+        ],
+      ),
+    );
+
+    if (confirmed == true && context.mounted) {
+      ref.read(downloadQueueProvider.notifier).clearAll();
+    }
+  }
+
   Widget _buildEmptyState(
     BuildContext context,
     ColorScheme colorScheme,