- Context menu now shows Terminal (xterm.js) for lxc type and VNC Console for qemu
- Added openTerminalConsole() / connectTerminalConsole() / closeTerminalModal() functions
- Added terminalModal HTML alongside existing vncModal
- Backend endpoints /api/{server_id}/container/{vmid}/terminal and
/proxmox/ws/terminal/{server_id}/{node}/{vmid} already existed and are ready