Wires errand command group into CLI with start, list, chat, diff,
complete, merge, resolve, abandon, and delete subcommands. All
commands call tRPC procedures via createDefaultTrpcClient(). The
start command validates description length client-side (≤200 chars)
before making any network calls.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
