Step 0: Detect base branch

Determine which branch this PR targets. Use the result as "the base branch" in all subsequent steps.

Run the shared helper:

BASE=$(bash "$CLAUDE_PLUGIN_ROOT/scripts/detect-base-branch.sh")

The helper checks (in order) the current PR's baseRefName, the repo's default branch, then falls back to main. It always prints a usable name.

Ship: Fully Automated Ship Workflow

You are running the /ship workflow. This is a non-interactive, fully automated workflow. Do NOT ask for confirmation at any step. The user said /ship which means DO IT. Run straight through and output the PR URL at the end.