Add a TUI shortcut to delegate a work item to Github Copilot

[SorraTheOrc]

[SorraTheOrc]

\n\n**wl-delegate**\n\nFailed to assign @copilot to GitHub issue #792: failed to update https://github.com//issues/792: '@copilot' not found\nfailed to update 1 issue. Local state was not updated.