Add program reminders and category filtering to the guide UI

Enhance health diagnostics with EPG quality and source metrics

src/css/topbar.css

@@ -149,6 +149,25 @@
   .theme-select:hover { border-color: var(--accent2); color: var(--accent2); }
   .theme-select option { background: #111; color: #eee; font-family: sans-serif; }
 
+  .category-filter {
+    background: transparent;
+    border: 1px solid var(--border-bright);
+    color: var(--text-dim);
+    font-family: var(--font-mono);
+    font-size: 10px;
+    letter-spacing: 0.08em;
+    padding: 4px 8px;
+    cursor: pointer;
+    text-transform: uppercase;
+    transition: all 0.15s;
+    flex-shrink: 0;
+    max-width: 180px;
+    -webkit-appearance: none;
+    appearance: none;
+  }
+  .category-filter:hover { border-color: var(--accent2); color: var(--accent2); }
+  .category-filter option { background: #111; color: #eee; font-family: sans-serif; }
+
       body { overflow: hidden; }
 
     .topbar {
@@ -159,6 +178,7 @@
     }
     .logo { font-size: 11px; }
     .clock { font-size: 14px; }
+    .category-filter { max-width: 100%; }
 
     .grid-wrapper { display: none; }
     .mobile-view { display: block; }