feat(audit): successful HTTP pushes finally write an audit row #5556

Surfaced by the Vapron deployment: its canonical repo had "no push logging" — because the product has none for its dominant transport. A successful Smart-HTTP push wrote no audit row; only rejections (push.rejected) and SSH attempts (git.push.ssh) were recorded, so "who pushed what, when" was unanswerable from the audit log on every Gluecron instance.

git.push.http rows now mirror the SSH path: pusher, repo, ip, user-agent, and the full ref list (name, old→new sha). Recorded as the authorized attempt (post access-check, post policy-gate); fire-and-forget so a failed audit write can never block a push. Root-cause fix upstream — every instance gets push logging on its next update instead of each box growing a local pre-receive hook.

Typecheck clean; push-policy + audit suites 47 pass.