fix: z-index overuse (#18192)

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

@@ -251,7 +251,7 @@
 
 <section>
   {#if assetInteraction.selectionActive}
-    <div class="fixed z-[100] top-0 start-0 w-full">
+    <div class="fixed top-0 start-0 w-full">
       <AssetSelectControlBar
         assets={assetInteraction.selectedAssets}
         clearSelect={() => cancelMultiselect(assetInteraction)}
@@ -289,9 +289,9 @@
       </AssetSelectControlBar>
     </div>
   {:else}
-    <div class="fixed z-[100] top-0 start-0 w-full">
+    <div class="fixed top-0 start-0 w-full">
       <ControlAppBar onClose={() => goto(previousRoute)} backIcon={mdiArrowLeft}>
-        <div class="-z-[1] bg-light" style="position:absolute;top:0;left:0;right:0;bottom:0;"></div>
+        <div class="absolute bg-light"></div>
         <div class="w-full flex-1 ps-4">
           <SearchBar grayTheme={false} value={terms?.query ?? ''} searchQuery={terms} />
         </div>