feat: selection mode timeline (#19734)

* feat: new page

* force multi-selection state

* fix: provider scoping

* Return selected assets

* lint

* lint

* simplify provider scope and drop drilling

* selection styling

mobile/lib/presentation/widgets/timeline/fixed/segment.model.dart

@@ -166,22 +166,22 @@ class _AssetTileWidget extends ConsumerWidget {
     BaseAsset asset,
   ) {
     final multiSelectState = ref.read(multiSelectProvider);
-    if (!multiSelectState.isEnabled) {
+
+    if (multiSelectState.forceEnable || multiSelectState.isEnabled) {
+      ref.read(multiSelectProvider.notifier).toggleAssetSelection(asset);
+    } else {
       ctx.pushRoute(
         AssetViewerRoute(
           initialIndex: assetIndex,
           timelineService: ref.read(timelineServiceProvider),
         ),
       );
-      return;
     }
-
-    ref.read(multiSelectProvider.notifier).toggleAssetSelection(asset);
   }
 
   void _handleOnLongPress(WidgetRef ref, BaseAsset asset) {
     final multiSelectState = ref.read(multiSelectProvider);
-    if (multiSelectState.isEnabled) {
+    if (multiSelectState.isEnabled || multiSelectState.forceEnable) {
       return;
     }
 
@@ -189,13 +189,35 @@ class _AssetTileWidget extends ConsumerWidget {
     ref.read(multiSelectProvider.notifier).toggleAssetSelection(asset);
   }
 
+  bool _getLockSelectionStatus(WidgetRef ref) {
+    final lockSelectionAssets = ref.read(
+      multiSelectProvider.select(
+        (state) => state.lockedSelectionAssets,
+      ),
+    );
+
+    if (lockSelectionAssets.isEmpty) {
+      return false;
+    }
+
+    return lockSelectionAssets.contains(asset);
+  }
+
   @override
   Widget build(BuildContext context, WidgetRef ref) {
+    final lockSelection = _getLockSelectionStatus(ref);
+
     return RepaintBoundary(
       child: GestureDetector(
-        onTap: () => _handleOnTap(context, ref, assetIndex, asset),
-        onLongPress: () => _handleOnLongPress(ref, asset),
-        child: ThumbnailTile(asset),
+        onTap: () => lockSelection
+            ? null
+            : _handleOnTap(context, ref, assetIndex, asset),
+        onLongPress: () =>
+            lockSelection ? null : _handleOnLongPress(ref, asset),
+        child: ThumbnailTile(
+          asset,
+          lockSelection: lockSelection,
+        ),
       ),
     );
   }