The command bodies in bin/quak.ts become functions in
src/cli-commands.ts that take their options and a context (output
streams, session directory, cache directory, session loader) and return
an exit code. bin/quak.ts wires them to commander and exits with that
code once stdout and stderr have drained; nothing below it calls
process.exit. test/cli/commands.test.ts drives the commands with a fake
client and temp directories. Output is unchanged.
Model: opus-5-5
