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/pages/dev/feat_in_development.page.dart

@@ -5,15 +5,43 @@ import 'package:drift/drift.dart' hide Column;
 import 'package:easy_localization/easy_localization.dart';
 import 'package:flutter/material.dart';
 import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
 import 'package:immich_mobile/extensions/build_context_extensions.dart';
 import 'package:immich_mobile/extensions/theme_extensions.dart';
 import 'package:immich_mobile/presentation/pages/dev/dev_logger.dart';
 import 'package:immich_mobile/providers/background_sync.provider.dart';
+import 'package:immich_mobile/providers/infrastructure/asset.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/db.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/platform.provider.dart';
+import 'package:immich_mobile/providers/user.provider.dart';
 import 'package:immich_mobile/routing/router.dart';
 
 final _features = [
+  _Feature(
+    name: 'Selection Mode Timeline',
+    icon: Icons.developer_mode_rounded,
+    onTap: (ctx, ref) async {
+      final user = ref.watch(currentUserProvider);
+      if (user == null) {
+        return Future.value();
+      }
+
+      final assets =
+          await ref.read(remoteAssetRepositoryProvider).getSome(user.id);
+
+      final selectedAssets = await ctx.pushRoute<Set<BaseAsset>>(
+        DriftAssetSelectionTimelineRoute(
+          lockedSelectionAssets: assets.toSet(),
+        ),
+      );
+
+      DLog.log(
+        "Selected ${selectedAssets?.length ?? 0} assets",
+      );
+
+      return Future.value();
+    },
+  ),
   _Feature(
     name: 'Sync Local',
     icon: Icons.photo_album_rounded,