fix: preserve stack primary asset selection (#31380)

* fix: preserve stack primary asset selection

* test: select stacked assets by id

* chore: limit dart formatting changes

* fix: address stack viewer review feedback

* fix: align stack ordering with server

* fix: keep stack primary asset first

---------

Co-authored-by: Daniel Dietzler <36593685+danieldietzler@users.noreply.github.com>
(cherry picked from commit 5a5d7be11084969c3c00a294ce6c0527042f88e7)

web/src/lib/components/asset-viewer/AssetViewer.svelte

@@ -291,16 +291,15 @@
     if (!stack || !withStacked || assetViewerManager.isShowEditor) {
       return;
     }
-    const assets = stack.assets;
-    const currentIndex = assets.findIndex(({ id }) => id === asset.id);
+    const currentIndex = stack.assets.findIndex(({ id }) => id === asset.id);
     if (currentIndex === -1) {
       return;
     }
     const nextIndex = direction === 'previous' ? currentIndex - 1 : currentIndex + 1;
-    if (nextIndex < 0 || nextIndex >= assets.length) {
+    if (nextIndex < 0 || nextIndex >= stack.assets.length) {
       return;
     }
-    cursor.current = assets[nextIndex];
+    cursor.current = stack.assets[nextIndex];
   };
 
   /**

web/src/routes/(user)/utilities/duplicates/[[photos=photos]]/[[assetId=id]]/DuplicatesCompareControl.svelte

@@ -94,7 +94,9 @@
   };
 
   const handleStack = () => {
-    onStack(assets);
+    const selectedAssets = assets.filter(({ id }) => selectedAssetIds.has(id));
+    const unselectedAssets = assets.filter(({ id }) => !selectedAssetIds.has(id));
+    onStack([...selectedAssets, ...unselectedAssets]);
   };
 
   const assetCursor = $derived({