refactor(web): consolidate timeline API - merge addAssets/updateAssets into upsertAssets (#23985)

web/src/routes/(user)/albums/[albumId=id]/[[photos=photos]]/[[assetId=id]]/+page.svelte

@@ -244,7 +244,7 @@
   };
 
   const handleUndoRemoveAssets = async (assets: TimelineAsset[]) => {
-    timelineManager.addAssets(assets);
+    timelineManager.upsertAssets(assets);
     await refreshAlbum();
   };
 

web/src/routes/(user)/favorites/[[photos=photos]]/[[assetId=id]]/+page.svelte

@@ -94,7 +94,7 @@
       <DeleteAssets
         menuItem
         onAssetDelete={(assetIds) => timelineManager.removeAssets(assetIds)}
-        onUndoDelete={(assets) => timelineManager.addAssets(assets)}
+        onUndoDelete={(assets) => timelineManager.upsertAssets(assets)}
       />
     </ButtonContextMenu>
   </AssetSelectControlBar>

web/src/routes/(user)/people/[personId]/[[photos=photos]]/[[assetId=id]]/+page.svelte

@@ -339,7 +339,7 @@
   };
 
   const handleUndoDeleteAssets = async (assets: TimelineAsset[]) => {
-    timelineManager.addAssets(assets);
+    timelineManager.upsertAssets(assets);
     await updateAssetCount();
   };
 

web/src/routes/(user)/photos/[[assetId=id]]/+page.svelte

@@ -69,12 +69,12 @@
 
   const handleLink: OnLink = ({ still, motion }) => {
     timelineManager.removeAssets([motion.id]);
-    timelineManager.updateAssets([still]);
+    timelineManager.upsertAssets([still]);
   };
 
   const handleUnlink: OnUnlink = ({ still, motion }) => {
-    timelineManager.addAssets([motion]);
-    timelineManager.updateAssets([still]);
+    timelineManager.upsertAssets([motion]);
+    timelineManager.upsertAssets([still]);
   };
 
   const handleSetVisibility = (assetIds: string[]) => {
@@ -153,7 +153,7 @@
       <DeleteAssets
         menuItem
         onAssetDelete={(assetIds) => timelineManager.removeAssets(assetIds)}
-        onUndoDelete={(assets) => timelineManager.addAssets(assets)}
+        onUndoDelete={(assets) => timelineManager.upsertAssets(assets)}
       />
       <SetVisibilityAction menuItem onVisibilitySet={handleSetVisibility} />
       <hr />

web/src/routes/(user)/utilities/geolocation/+page.svelte

@@ -63,7 +63,7 @@
       }),
     );
 
-    timelineManager.updateAssets(updatedAssets);
+    timelineManager.upsertAssets(updatedAssets);
 
     handleDeselectAll();
   };