feat(web): /discover scrolls only the results, not the chrome

Restructures the page as a full-height flex column so the persistent
chrome (DiscoverTabs, search input, facet tabs, header) stays anchored
at the top and only the result grid scrolls. Same treatment for the
empty-state SuggestionFeed.

Main retains overflow-y-auto for other pages, but with h-full + flex-col
+ min-h-0 on the inner scroll region this page contains its own
overflow and main's scroll never triggers — search field + facet tabs
remain visible while you browse results.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/routes/discover/+page.svelte

@@ -115,9 +115,16 @@
   ];
 </script>
 
-<DiscoverTabs />
+<!--
+  Page layout: a full-height flex column so the persistent chrome
+  (DiscoverTabs, search input, facet tabs) stays anchored at the top
+  while only the result grid scrolls. Main has overflow-y-auto, but
+  with h-full + flex-col + min-h-0 on the scroll region, this page
+  contains its own overflow and main's scroll never triggers.
+-->
+<div class="flex h-full flex-col gap-4">
+  <DiscoverTabs />
 
-<div class="space-y-6 pt-6">
   <input
     type="search"
     aria-label="Search Lidarr"
@@ -127,7 +134,9 @@
   />
 
   {#if debouncedQ === ''}
+    <div class="min-h-0 flex-1 overflow-y-auto pb-4">
       <SuggestionFeed />
+    </div>
   {:else}
     <header class="space-y-1">
       <h2 class="font-display text-2xl font-medium text-text-primary">
@@ -157,6 +166,7 @@
       </ul>
     </nav>
 
+    <div class="min-h-0 flex-1 overflow-y-auto pb-4">
       {#if query.isError}
         <ApiErrorBanner error={query.error} onRetry={query.refetch} />
       {:else if query.isPending}
@@ -177,6 +187,7 @@
           {/each}
         </div>
       {/if}
+    </div>
   {/if}
 </div>