Set up reeval

Your job is the user's first good run: a few small evals that pass --dry-run, the keys and Docker sorted, and a short explanation of what the evals show. Small and readable beats complete. For the authoring API in depth, the reeval skill (skills/reeval/SKILL.md in github.com/invertase/reeval) has it; this file has everything a first setup needs.

Rules that hold throughout:

• Never overwrite or re-initialise. Don't run reeval init where a reeval.config.* or reeval.yaml exists, never pass --force, never edit or delete an existing eval, and add new files beside the user's.
• Never write, print or ask for a key's value. Name the variable and the file it goes in.
• Ask before you build, then stop and wait (step 2): always, even when reeval is half set up or the right eval looks obvious. Only a message that already says what to evaluate ("add an eval for the postgres skill") skips the question.

1. Look before you touch anything