Fix VirtViewer detection on Windows + manual path override

VirtViewer's installer folder name includes the version number
(e.g. "VirtViewer v11.0-256"), so the previous hardcoded path never
matched a real install. Now scans Program Files for any VirtViewer*
folder, and adds a Settings dialog (Windows only) to pick the
remote-viewer.exe path manually as a fallback.

src/renderer/styles.css

@@ -292,3 +292,59 @@ body.vms-page {
   margin-top: 0.5rem;
   color: #3a4a60;
 }
+
+/* ── Settings modal ───────────────────────────────────────── */
+.modal-overlay {
+  position: fixed;
+  inset: 0;
+  background: rgba(5, 8, 16, 0.65);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  z-index: 10;
+}
+
+.modal-card {
+  width: 420px;
+  max-width: 90vw;
+  background: var(--bg-card);
+  border: 1px solid var(--border);
+  border-radius: 14px;
+  padding: 1.6rem 1.7rem;
+  box-shadow: 0 24px 60px rgba(0,0,0,0.55);
+}
+
+.modal-card h3 {
+  font-size: 1rem;
+  font-weight: 600;
+  margin-bottom: 0.6rem;
+}
+
+.modal-card .hint {
+  font-size: 0.8rem;
+  color: var(--muted);
+  margin-bottom: 1.1rem;
+  line-height: 1.5;
+}
+
+.path-display {
+  padding: 0.6rem 0.85rem;
+  background: var(--bg-input);
+  border: 1px solid var(--border);
+  border-radius: 7px;
+  font-size: 0.82rem;
+  color: var(--text);
+  word-break: break-all;
+}
+
+.modal-actions {
+  display: flex;
+  gap: 0.5rem;
+  justify-content: flex-end;
+  margin-top: 1.4rem;
+}
+
+.modal-actions .modal-close {
+  width: auto;
+  padding: 0.42rem 1rem;
+}

src/renderer/vms.html

@@ -14,6 +14,7 @@
     <div class="page-header">
       <h2>Virtuelle Maschinen</h2>
       <div class="header-actions">
+        <button id="settingsBtn" class="btn-secondary hidden" title="Viewer-Pfad einstellen">⚙ Einstellungen</button>
         <button id="refreshBtn" class="btn-secondary" title="Liste aktualisieren">↻ Aktualisieren</button>
         <button id="logoutBtn" class="btn-secondary">Abmelden</button>
       </div>
@@ -42,6 +43,26 @@
 
   </div>
 
+  <!-- Settings modal (Windows only — VirtViewer's install folder name changes per version) -->
+  <div id="settingsOverlay" class="modal-overlay hidden">
+    <div class="modal-card">
+      <h3>Viewer-Pfad</h3>
+      <p class="hint">
+        Wird VirtViewer (remote-viewer.exe) nicht automatisch gefunden, kannst du hier
+        den Pfad zur .exe manuell festlegen.
+      </p>
+      <div class="field">
+        <label>Aktueller Pfad</label>
+        <div id="viewerPathDisplay" class="path-display">automatisch erkannt</div>
+      </div>
+      <div class="modal-actions">
+        <button id="browseViewerBtn" class="btn-secondary">Durchsuchen…</button>
+        <button id="resetViewerBtn" class="btn-secondary">Zurücksetzen</button>
+        <button id="closeSettingsBtn" class="btn-primary modal-close">Schließen</button>
+      </div>
+    </div>
+  </div>
+
   <script src="vms.js"></script>
 </body>
 </html>

src/renderer/vms.js

@@ -6,6 +6,9 @@ const emptyEl   = document.getElementById('emptyState');
 const errorEl   = document.getElementById('error');
 const noticeEl  = document.getElementById('notice');
 const refreshBtn = document.getElementById('refreshBtn');
+const settingsBtn = document.getElementById('settingsBtn');
+const settingsOverlay = document.getElementById('settingsOverlay');
+const viewerPathDisplay = document.getElementById('viewerPathDisplay');
 
 document.getElementById('logoutBtn').addEventListener('click', async () => {
   await api.proxmox.logout();
@@ -13,6 +16,42 @@ document.getElementById('logoutBtn').addEventListener('click', async () => {
 
 refreshBtn.addEventListener('click', () => loadVMs());
 
+// ── Settings (Windows only — VirtViewer's install folder name carries the
+//    version number, so auto-detection can miss non-standard installs) ──
+
+initSettings();
+
+async function initSettings() {
+  const platform = await api.settings.platform();
+  if (platform !== 'win32') return;
+
+  settingsBtn.classList.remove('hidden');
+  settingsBtn.addEventListener('click', openSettings);
+  document.getElementById('closeSettingsBtn').addEventListener('click', closeSettings);
+  document.getElementById('browseViewerBtn').addEventListener('click', async () => {
+    const chosen = await api.settings.browseViewerPath();
+    if (chosen) await refreshViewerPathDisplay();
+  });
+  document.getElementById('resetViewerBtn').addEventListener('click', async () => {
+    await api.settings.clearViewerPath();
+    await refreshViewerPathDisplay();
+  });
+}
+
+async function openSettings() {
+  await refreshViewerPathDisplay();
+  settingsOverlay.classList.remove('hidden');
+}
+
+function closeSettings() {
+  settingsOverlay.classList.add('hidden');
+}
+
+async function refreshViewerPathDisplay() {
+  const viewerPath = await api.settings.getViewerPath();
+  viewerPathDisplay.textContent = viewerPath || 'automatisch erkannt';
+}
+
 // ── Load on mount ─────────────────────────────────────────
 
 async function loadVMs() {