feat: enhance download functionality with selectable log types and command history management

uart_example/index.css

@@ -896,3 +896,57 @@ body.light-theme .session-item.active {
 .hidden {
   display: none !important;
 }
+
+/* Download Group Control Styling */
+.download-group {
+  display: flex;
+  align-items: center;
+  gap: 0.25rem;
+  background-color: var(--bg-input);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius-md);
+  padding: 3px 6px 3px 3px;
+  height: 48px;
+  box-shadow: var(--shadow-sm);
+  transition: border-color var(--transition-fast), background-color var(--transition-fast);
+}
+
+.download-group:hover {
+  border-color: var(--border-hover);
+}
+
+.download-group .download-btn {
+  height: 40px;
+  width: 40px;
+  border-radius: 6px;
+  box-shadow: none;
+}
+
+.download-group .download-btn:hover:not(:disabled) {
+  transform: none;
+}
+
+.download-select-wrapper {
+  width: 105px;
+  flex-shrink: 0;
+}
+
+.download-select-wrapper select {
+  background-color: transparent !important;
+  border: none !important;
+  padding: 0.4rem 1.75rem 0.4rem 0.5rem !important;
+  font-weight: 600;
+  font-size: 0.85rem;
+  color: var(--text-main);
+  box-shadow: none !important;
+}
+
+.download-select-wrapper select option {
+  background-color: var(--bg-panel);
+  color: var(--text-main);
+}
+
+.download-select-wrapper::after {
+  right: 0.5rem;
+}
+