UI polish: refresh button, negative thumbnail cache, and style fixes

- Add refresh button to browser toolbar to re-fetch current folder
- Cache "no thumbnail" results to avoid repeated slow SMB lookups
- Fix list view fallback icon sizing for files without album art
- Fix view toggle button hover (no background/scale on hover)
- Skip re-render when clicking already-active view mode button

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

media_server/static/css/styles.css

@@ -1214,8 +1214,8 @@
 
 .view-toggle-btn:hover {
     color: var(--text-primary);
-    background: var(--border);
-    transform: none;
+    background: transparent !important;
+    transform: none !important;
 }
 
 .view-toggle-btn.active {
@@ -1223,6 +1223,10 @@
     background: var(--bg-primary);
 }
 
+.browser-refresh-btn {
+    margin-left: 0.35rem;
+}
+
 .view-toggle-btn svg {
     fill: currentColor;
 }

media_server/static/index.html

@@ -164,6 +164,9 @@
                             <svg viewBox="0 0 24 24" width="18" height="18"><path d="M3 4h18v2H3V4zm0 7h18v2H3v-2zm0 7h18v2H3v-2z"/></svg>
                         </button>
                     </div>
+                    <button class="view-toggle-btn browser-refresh-btn" id="refreshBtn" onclick="refreshBrowser()" data-i18n-title="browser.refresh" title="Refresh">
+                        <svg viewBox="0 0 24 24" width="18" height="18"><path fill="currentColor" d="M17.65 6.35A7.958 7.958 0 0012 4c-4.42 0-7.99 3.58-7.99 8s3.57 8 7.99 8c3.73 0 6.84-2.55 7.73-6h-2.08A5.99 5.99 0 0112 18c-3.31 0-6-2.69-6-6s2.69-6 6-6c1.66 0 3.14.69 4.22 1.78L13 11h7V4l-2.35 2.35z"/></svg>
+                    </button>
                     <button class="browser-play-all-btn" id="playAllBtn" onclick="playAllFolder()" data-i18n-title="browser.play_all" title="Play All" style="display: none;">
                         <svg viewBox="0 0 24 24" width="16" height="16"><path fill="currentColor" d="M8 5v14l11-7z"/></svg>
                         <span data-i18n="browser.play_all">Play All</span>

media_server/static/js/app.js

@@ -1873,11 +1873,16 @@ async function loadThumbnail(imgElement, fileName) {
         } else {
             // Fallback to icon (204 = no thumbnail available)
             const parent = imgElement.parentElement;
+            const isList = parent.classList.contains('browser-list-icon');
             imgElement.remove();
-            const icon = document.createElement('div');
-            icon.className = 'browser-icon';
-            icon.textContent = '🎵';
-            parent.insertBefore(icon, parent.firstChild);
+            if (isList) {
+                parent.textContent = '🎵';
+            } else {
+                const icon = document.createElement('div');
+                icon.className = 'browser-icon';
+                icon.textContent = '🎵';
+                parent.insertBefore(icon, parent.firstChild);
+            }
         }
     } catch (error) {
         console.error('Error loading thumbnail:', error);
@@ -2008,7 +2013,16 @@ function nextPage() {
     }
 }
 
+function refreshBrowser() {
+    if (currentFolderId) {
+        browsePath(currentFolderId, currentPath, currentOffset);
+    } else {
+        loadMediaFolders();
+    }
+}
+
 function setViewMode(mode) {
+    if (mode === viewMode) return;
     viewMode = mode;
     localStorage.setItem('mediaBrowser.viewMode', mode);