v0.4.1: app filtering + clickable dashboard stat cards

Add filter bar (Mind/Futó/Leállítva/Telepíthető) to Alkalmazások page with
URL-based filter persistence. Dashboard stat cards are now clickable links
that navigate to the filtered stacks view.

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

controller/internal/web/templates/style.css

@@ -822,6 +822,54 @@ select.form-control option { background: var(--bg-secondary); color: var(--text-
     border-color: rgba(218, 54, 51, 0.3);
 }
 
+/* --- Filter bar --- */
+.filter-bar {
+    display: flex;
+    gap: 0.5rem;
+    margin-bottom: 1.5rem;
+    flex-wrap: wrap;
+}
+
+.filter-btn {
+    padding: 0.4rem 1rem;
+    border-radius: 20px;
+    border: 1px solid var(--border-color);
+    background: var(--bg-secondary);
+    color: var(--text-secondary);
+    cursor: pointer;
+    font-size: 0.85rem;
+    font-family: inherit;
+    transition: all 0.2s;
+}
+
+.filter-btn:hover {
+    border-color: var(--accent-blue);
+    color: var(--text-primary);
+}
+
+.filter-btn.active {
+    background: var(--accent-blue);
+    border-color: var(--accent-blue);
+    color: #fff;
+}
+
+.filter-count {
+    opacity: 0.7;
+    font-size: 0.8rem;
+}
+
+/* Clickable stat cards */
+a.stat-card {
+    text-decoration: none;
+    color: inherit;
+    transition: transform 0.15s, box-shadow 0.15s;
+}
+
+a.stat-card:hover {
+    transform: translateY(-2px);
+    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
+}
+
 /* Clickable cards */
 [data-href] { cursor: pointer; }