Adds a "Send Key" dropdown menu to the console toolbar for keys that
browsers intercept before JavaScript can capture them (Print Screen,
Scroll Lock, Pause/Break). Also includes Escape, Tab, Caps Lock,
Num Lock, and Ctrl+Alt+Del.
Each menu item sends a press+release scancode pair directly over the
WebSocket, bypassing browser key capture entirely. This enables
activating downstream KVM switch menus (e.g., Avocent OSCAR via
Print Screen) from the blekin interface.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>