"""The `dev` domain — developer environment and self-diagnosis.

Per the domain map, this eventually holds install-rust, install-godot,
worktree-setup, perf-baseline and clerk-review. It starts with `selftest`,
which exists because the streaming and job machinery had nothing slow enough to
exercise: every other command in reach finishes in milliseconds, so "does a long
run stream, and can I tail it, and does its failure survive?" was unanswerable
except by argument.
"""