Move store chips to own row below filter input

Filter bar now has two rows: text filter + count on top,
store toggle chips on the bottom. Chips wrap on narrow screens.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/client/src/routes/results/+page.svelte

@@ -150,7 +150,8 @@
 
   <!-- Filters row -->
   {#if !loading && results.length > 0}
-    <div class="flex-shrink-0 border-b border-surface-border px-6 py-2 flex items-center gap-3">
+    <div class="flex-shrink-0 border-b border-surface-border px-6 py-2 space-y-2">
+      <div class="flex items-center gap-3">
         <div class="relative flex-1">
           <svg class="absolute left-2.5 top-1/2 -translate-y-1/2 w-3 h-3 text-text-tertiary"
             fill="none" viewBox="0 0 24 24" stroke="currentColor" stroke-width="2">
@@ -160,8 +161,12 @@
             class="w-full pl-8 pr-3 py-1 bg-surface border border-surface-border rounded text-xs
                    text-text-primary placeholder-text-tertiary focus:border-accent/50 focus:outline-none transition-colors" />
         </div>
+        <span class="text-2xs text-text-tertiary whitespace-nowrap">
+          {filteredAndSorted().length} of {results.length}
+        </span>
+      </div>
 
-      <div class="flex items-center gap-1.5">
+      <div class="flex items-center gap-1.5 flex-wrap">
         {#each storeNames() as name}
           <button
             onclick={() => toggleStore(name)}
@@ -184,10 +189,6 @@
           </button>
         {/each}
       </div>
-
-      <span class="text-2xs text-text-tertiary whitespace-nowrap">
-        {filteredAndSorted().length} of {results.length}
-      </span>
     </div>
   {/if}