cdd: Command for Claude Code

Run a pre-PR checklist for the current branch. Compare against the base branch to identify all changes. This is a verification session: it runs CI gates, code-reviews the diff, and reconciles documentation against the changes.

This session is fresh and separate from the implementation session by design, so that the verification work is not biased by the context that produced the change. Any "propose to the user" step in this command is a proposal to the user running this session.

0. Resolve the base branch

BASE_BRANCH=$(cdd-state get base_branch 2>/dev/null)
# With no base recorded, look for a code-host adapter: project, then machine; the first file present wins.
[ -z "$BASE_BRANCH" ] && for c in .cdd/code-host ~/.cdd/adapters/code-host; do [ -e "$c" ] && { CODE_HOST="$c"; break; }; done

If $CODE_HOST is set, check it before using it: the file is executable, and "$CODE_HOST" describe exits 0, parses as JSON, and reports capability code-host and contract 1. If any of that fails, the adapter is installed but broken — say so in one line naming its path, and stop; do not fall back to git, because an installed adapter declares which code host this project uses. If it is usable, say in one line which adapter serves, then take its answer:

BASE_BRANCH=$("$CODE_HOST" default-branch | jq -r '.branch // empty')   # exit 3 (unsupported) or a failure leaves it empty

Whatever is still empty falls back to git, as a bare branch name:

BASE_BRANCH=${BASE_BRANCH:-$(git symbolic-ref --quiet --short refs/remotes/origin/HEAD 2>/dev/null | sed 's#^origin/##')}
BASE_BRANCH=${BASE_BRANCH:-main}

This reads the task's recorded base branch — the branch it was cut from and merges back into — and falls back to the code host's default branch when none was recorded — through the code-host adapter when one is installed, else from git (unchanged behaviour for single-integration-branch projects). Use $BASE_BRANCH wherever main/origin/main appears in git commands below.