The drawer's surface_validate area now leads with a row of operator
vitals computed from data already in the response:
- Temp: drive temperature with cool/warm/hot colour (≥48 red, ≥42 yellow)
- Speed: live MB/s, NULL until second progress sample arrives
- Elapsed: time since stage started_at
- ETA: extrapolated from overall progress; suppressed under 0.5%
to avoid the "47 days remaining" artefact early in pattern 1
Live MB/s comes from a new bb_mbps column on burnin_stages, computed
in the badblocks parser as (delta_overall_pct / 800) * size_bytes / dt.
Skipped on phase transitions (per-phase pct resets) and sub-second
samples (noisy).
Drawer endpoint now passes drive.temperature_c through; JS stashes
the latest drive object in _DRAWER_LAST_DRIVE so the burn-in renderer
can pull it for the vitals row without changing call signatures.
Tightened table CSS in this same session is unrelated and shipped
already in earlier rounds via the bind-mounted app.css.