Fix search, branding, header centering, and card-based feed layout

- Search box now fills navbar center with max-width 400px
- Dropdown items have more padding (p-4) and hover contrast
- Branding uses cross-browser gradient text with visible tagline
- Navbar centers tabs + search together in navbar-center
- Feed redesigned as responsive card grid (cover-centered, details below)
- Cards show large cover art with aspect-ratio:1, fallback SVG on 404
- Artist name, title, type badge, and date positioned under cover

src/main/resources/templates/fragments/search-results.html

@@ -1,18 +1,18 @@
-<div class="bg-base-100 shadow-xl border border-base-300 rounded-box mt-1" style="max-height:18rem;overflow-y:auto">
+<div class="bg-base-100 shadow-xl border border-base-300 rounded-box mt-1" style="max-height:24rem;overflow-y:auto">
   {#if artists.isEmpty()}
-    <div class="p-4 text-sm text-center" style="color:var(--bc);opacity:0.5">No artists found</div>
+    <div class="p-6 text-sm text-center" style="color:var(--bc);opacity:0.5">No artists found</div>
   {#else}
     {#for artist in artists}
-    <div class="search-dropdown-item p-3 border-b border-base-200" style="display:flex;align-items:center;justify-content:space-between">
-      <div class="flex-1 min-w-0 mr-2">
-        <div style="display:flex;align-items:center;gap:0.5rem">
-          <span style="font-weight:600;font-size:0.875rem">{artist.name}</span>
+    <div class="p-4 border-b border-base-200 last:border-b-0" style="display:flex;align-items:center;justify-content:space-between;transition:background 0.15s" onmouseover="this.style.background='color-mix(in srgb, var(--p) 8%, transparent)'" onmouseout="this.style.background=''">
+      <div class="flex-1 min-w-0 mr-3">
+        <div style="display:flex;align-items:center;gap:0.5rem;margin-bottom:0.25rem">
+          <span style="font-weight:600;font-size:0.9rem">{artist.name}</span>
           {#if artist.type}
             <span class="badge badge-ghost badge-xs">{artist.type}</span>
           {/if}
         </div>
         {#if artist.disambiguation}
-          <div style="font-size:0.75rem;color:var(--bc);opacity:0.5;overflow:hidden;text-overflow:ellipsis;white-space:nowrap">{artist.disambiguation}</div>
+          <div style="font-size:0.8rem;color:var(--bc);opacity:0.55;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;margin-bottom:0.15rem">{artist.disambiguation}</div>
         {/if}
         {#if artist.area}
           <div style="font-size:0.75rem;color:var(--bc);opacity:0.4">{artist.area}</div>
@@ -20,12 +20,13 @@
       </div>
       <div style="flex-shrink:0">
         {#if artist.alreadyTracked}
-          <span class="badge badge-success badge-sm gap-1">
+          <span class="badge badge-success badge-sm gap-1" style="padding:0.3rem 0.6rem">
             <svg class="icon-xs" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="3"><polyline points="20 6 9 17 4 12"/></svg>
             Added
           </span>
         {#else}
-          <button class="btn btn-primary btn-xs"
+          <button class="btn btn-primary btn-sm"
+                  style="min-height:0;height:2rem;padding:0 0.75rem"
                   hx-post="/api/artists/{artist.mbid}/track"
                   hx-target="#search-results"
                   hx-swap="innerHTML"