auto-claude: subtask-1-1 - Add focusedIndex state and arrow key navigation logic

- Added focusedIndex state to track keyboard focus
- Enhanced handleKeyDown to support ArrowDown, ArrowUp, Enter, and Escape keys
- Added visual focus indicator with orange ring (ring-2 ring-orange-500)
- Implemented aria-activedescendant for screen reader support
- Added unique IDs to language options for accessibility
- Reset focusedIndex when dropdown opens/closes

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.auto-claude-status

@@ -0,0 +1,25 @@
+{
+  "active": true,
+  "spec": "011-languageswitcher-arrow-key-navigation",
+  "state": "planning",
+  "subtasks": {
+    "completed": 0,
+    "total": 0,
+    "in_progress": 1,
+    "failed": 0
+  },
+  "phase": {
+    "current": "Add Arrow Key Navigation",
+    "id": null,
+    "total": 1
+  },
+  "workers": {
+    "active": 0,
+    "max": 1
+  },
+  "session": {
+    "number": 2,
+    "started_at": "2026-01-25T06:26:06.270781"
+  },
+  "last_update": "2026-01-25T06:29:49.299484"
+}