i18n: localize per-metric status labels (Poor/Elevated/…) across all locales

[mzspicoli]

Summary

First — thanks again for merging PR #33 (the Portuguese translation)! It's working great. While using it I noticed one remaining spot that didn't pick up the translation: the small status pill inside each metric card (CO₂, PM2.5, humidity, temperature, …) was always rendering "Poor" / "Elevated" / "Warm" / etc. in English regardless of the configured language. I reproduced the same thing with es and de, so it's not pt-specific.

Here's the bug with language: pt — header badge says "Ruim" (translated) but the per-metric pills still say "Poor":

Root cause: METRIC_DEFS.labels held English display strings, and _getMetricStatus() returned them verbatim — the only place that bypassed the _t('status', …) lookup that _getOverallStatus() already uses for the header badge.

Fix: smallest viable patch that reuses the existing translation machinery — no new helpers, no new translation groups, no change to thresholds, recommendation cascade, or overall-status logic:

1. Rename METRIC_DEFS[*].labels → labelKeys and lowercase the values into status translation keys ('Poor' → 'poor', 'Too Dry' → 'too_dry', etc.).
2. _getMetricStatus() resolves the key through this._t('status', key) — the same path the header badge already uses.
3. Extend each locale's status group with the previously-untranslated keys: safe, low, high, elevated, clean, too_dry, dry, comfortable, humid, too_humid, cold, cool, warm, hot. English values match what was in METRIC_DEFS.labels so en behavior is byte-identical.
4. Bumps CARD_VERSION to 2.9.2.

Spanish, French, German, and Portuguese values follow the same domain vocabulary already used elsewhere in those locales (e.g. pt uses "Muito Seco" / "Muito Úmido" matching the existing recommendation.too_dry / too_humid).

Test plan

All 368 tests pass (node test.js) — 360 existing + 8 new covering the bug:

• en CO₂ 2000 ppm → Poor (unchanged)
• pt CO₂ 2000 ppm → Ruim
• es CO₂ 2000 ppm → Malo
• de PM2.5 50 µg/m³ → Schlecht
• fr CO₂ 1200 ppm → Élevé
• pt humidity 20% → Muito Seco
• pt temperature 23 °C → Morno
• es temperature 23 °C → Cálido
• Existing English assertions for _getCO2Status / _getMetricStatus / _getTempStatus continue to pass (English fallback is byte-identical to the old hard-coded labels).

Tested locally in Home Assistant with language: pt — the per-metric pill now matches the header badge ("Ruim" instead of "Poor"). Screenshot above shows the pre-fix state.

🤖 Generated with Claude Code / I reviewed each translation before opening :)