Add v9.1.1: Device registry and remote blocking system

- Implement DeviceRegistry for remote device management
- Add dashboard for device tracking and blocking
- Remote device blocking capability with admin control
- Support for device aliasing and notes
- Enhanced device management interface
- Dashboard with real-time device status
- Configurable registry URL in build config

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

dashboard/public/styles.css

@@ -0,0 +1,89 @@
+:root {
+  font-family: 'Segoe UI', Tahoma, sans-serif;
+  color: #202124;
+  background: #f7f7f7;
+}
+
+body {
+  margin: 0;
+  padding: 2rem;
+}
+
+header {
+  margin-bottom: 1rem;
+}
+
+header h1 {
+  margin-bottom: 0.2rem;
+}
+
+.actions {
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+  margin-bottom: 1rem;
+}
+
+button {
+  border: none;
+  background: #4285f4;
+  color: #fff;
+  padding: 0.5rem 1rem;
+  border-radius: 4px;
+  cursor: pointer;
+  font-size: 0.9rem;
+}
+
+button.danger {
+  background: #d93025;
+}
+
+button.primary {
+  background: #1a73e8;
+}
+
+.table-wrapper {
+  overflow-x: auto;
+  background: #fff;
+  border-radius: 8px;
+  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
+}
+
+table {
+  width: 100%;
+  border-collapse: collapse;
+}
+
+th, td {
+  padding: 0.8rem;
+  text-align: left;
+  border-bottom: 1px solid #eee;
+}
+
+th {
+  background: #fafafa;
+  font-weight: 600;
+}
+
+tr.blocked {
+  background: #fff4f4;
+}
+
+.actions-cell button {
+  margin-right: 0.3rem;
+}
+
+.alias {
+  font-weight: 600;
+}
+
+.device-name {
+  font-size: 0.85rem;
+  color: #5f6368;
+}
+
+.empty {
+  text-align: center;
+  padding: 2rem;
+  color: #5f6368;
+}