v2.11.0 — Alert chips, auto-expand, and full NOx support

✨ New Features

Alert chips in compact view (#40)

When the card is collapsed (display: compact or expandable), small colored chips now appear next to the status badge naming exactly which sensors are out of range — most severe first, with CO and radon always leading, capped at 4 plus a +N overflow pill. Chips are localized (en/es/fr/de/pt) and on by default; disable with compact_alerts: false. Atmospheric pressure is informational and never produces a chip.

Auto-expand (#40)

With display: expandable, add auto_expand: true and the card opens automatically while any sensor reads out of range, then collapses once readings have stayed normal for 5 minutes (hysteresis prevents flapping at threshold boundaries). A manual tap takes over so the automation never fights you.

Outdoor NOx + Sensirion NOx Index (#41)

• New outdoor_nox_entity option with the full outdoor treatment: dashed comparison line on the graph, (out: …) value suffix, outdoor-only promotion, editor field.
• The card now auto-detects whether your NOx sensor reports absolute ppb or the Sensirion SGP41 NOx Index (AirGradient ONE / Open Air, ESPHome sgp4x) — force with nox_unit: index|ppb if needed.
• NOx Index tiers follow Sensirion's integration guidance and AirGradient's dashboard bands: Excellent <5, Good 5–20, Moderate 20–150, Elevated 150–300, Poor >300 (the index baselines at 1 in clean air, unlike the VOC Index's 100).
• Absolute-ppb defaults re-anchored to real standards: [20, 53, 100, 360] (≈WHO 2021 IT-1, EPA annual NAAQS, EPA 1-hour NAAQS, EPA AQI Unhealthy breakpoint). Override with nox_thresholds if you'd customized around the old values.
• Sensors reporting µg/m³ now display their real unit (set nox_thresholds in your unit; for NO₂, 1 ppb ≈ 1.88 µg/m³).

📝 Docs

• README: NOx threshold tables (both modes), VOC Index table, tvoc_unit/nox_unit/pm4_entity/nox_entity config rows, Portuguese added to the language list.

🧪 Tests

397 → 477 assertions, all passing. Every change above is pinned by tests, including the history plumbing and the hass-setter auto-expand wiring.

Full Changelog: v2.10.0...v2.11.0