working tree, staging, commit — the model ai breaks first

Final drill. Write safe_to_commit(status) that decides whether the current staged set is safe to commit. Rules:

• If anything in status["staged"] starts with .env (any case), return ("block", "secrets staged").
• If status["staged"] is empty, return ("block", "nothing staged").
• Otherwise return ("ok", f"{n} files staged") where n is the count of staged files.

Then the script will exercise three cases and print each result.

Expected output:

ok: 2 files staged
block: secrets staged
block: nothing staged