release: v1.6.1 - Weather forecasts, sun times, air quality

- Weather fetch now returns 7-day forecasts with UV index
- New /volatile/fetch/sun/{city} endpoint for sunrise/sunset
- New /volatile/fetch/air_quality/{city} endpoint for AQI and pollutants
- OpenMeteoProvider now implements AirQualityProvider interface

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/apis/base.py

@@ -44,14 +44,18 @@ class CurrentWeather:
     condition_text: str  # Human-readable description
     timestamp: datetime
     location: str  # City/location name
+    uv_index: Optional[float] = None  # UV index 0-11+
 
     def to_text(self) -> str:
         """Generate natural language description."""
-        return (
-            f"Currently {self.temperature:.1f}°C "
-            f"({self.condition_text}) in {self.location}. "
+        parts = [
+            f"Currently {self.temperature:.1f}°C",
+            f"({self.condition_text}) in {self.location}.",
             f"Humidity {self.humidity}%, wind {self.wind_speed:.0f} km/h."
-        )
+        ]
+        if self.uv_index is not None:
+            parts.append(f"UV index: {self.uv_index:.0f}.")
+        return " ".join(parts)
 
 
 @dataclass
@@ -64,6 +68,14 @@ class DayForecast:
     condition_text: str
     precipitation_chance: Optional[int]  # Percentage 0-100
     precipitation_mm: Optional[float]
+    uv_index_max: Optional[float] = None  # Max UV index for the day
+
+    def to_text(self) -> str:
+        """Generate natural language description."""
+        date_str = self.date.strftime("%A")  # Day name
+        precip = f", {self.precipitation_chance}% rain" if self.precipitation_chance else ""
+        uv = f", UV {self.uv_index_max:.0f}" if self.uv_index_max else ""
+        return f"{date_str}: {self.temp_high:.0f}°/{self.temp_low:.0f}°C, {self.condition_text}{precip}{uv}"
 
 
 @dataclass
@@ -84,6 +96,78 @@ class GeoLocation:
     admin_area: Optional[str] = None  # State/province
 
 
+@dataclass
+class SunTimes:
+    """Sunrise/sunset times for a location."""
+    location: str
+    date: datetime
+    sunrise: datetime
+    sunset: datetime
+    daylight_duration: int  # seconds
+    solar_noon: Optional[datetime] = None
+
+    def to_text(self) -> str:
+        """Generate natural language description."""
+        sunrise_str = self.sunrise.strftime("%H:%M")
+        sunset_str = self.sunset.strftime("%H:%M")
+        hours = self.daylight_duration // 3600
+        minutes = (self.daylight_duration % 3600) // 60
+        return (
+            f"Sun times for {self.location} on {self.date.strftime('%A %d %B')}: "
+            f"Sunrise at {sunrise_str}, sunset at {sunset_str}. "
+            f"Daylight duration: {hours}h {minutes}m."
+        )
+
+
+@dataclass
+class AirQuality:
+    """Air quality measurements for a location."""
+    location: str
+    timestamp: datetime
+    aqi_european: Optional[int]  # European AQI 0-500+
+    aqi_us: Optional[int]  # US AQI 0-500+
+    pm2_5: Optional[float]  # µg/m³
+    pm10: Optional[float]  # µg/m³
+    ozone: Optional[float]  # µg/m³
+    nitrogen_dioxide: Optional[float]  # µg/m³
+    sulphur_dioxide: Optional[float]  # µg/m³
+    carbon_monoxide: Optional[float]  # µg/m³
+    # Pollen (European data only, seasonal)
+    pollen_grass: Optional[float] = None
+    pollen_birch: Optional[float] = None
+    pollen_alder: Optional[float] = None
+
+    def to_text(self) -> str:
+        """Generate natural language description."""
+        parts = [f"Air quality in {self.location}:"]
+        if self.aqi_european is not None:
+            level = self._aqi_level(self.aqi_european)
+            parts.append(f"European AQI {self.aqi_european} ({level}).")
+        if self.pm2_5 is not None:
+            parts.append(f"PM2.5: {self.pm2_5:.1f} µg/m³.")
+        if self.pm10 is not None:
+            parts.append(f"PM10: {self.pm10:.1f} µg/m³.")
+        if self.ozone is not None:
+            parts.append(f"Ozone: {self.ozone:.1f} µg/m³.")
+        return " ".join(parts)
+
+    @staticmethod
+    def _aqi_level(aqi: int) -> str:
+        """Convert AQI to human-readable level."""
+        if aqi <= 20:
+            return "good"
+        elif aqi <= 40:
+            return "fair"
+        elif aqi <= 60:
+            return "moderate"
+        elif aqi <= 80:
+            return "poor"
+        elif aqi <= 100:
+            return "very poor"
+        else:
+            return "hazardous"
+
+
 # =============================================================================
 # News Models
 # =============================================================================
@@ -163,6 +247,11 @@ class WeatherProvider(ABC):
         """Get weather forecast for a location."""
         pass
 
+    @abstractmethod
+    async def get_sun_times(self, location: GeoLocation) -> SunTimes:
+        """Get sunrise/sunset times for today."""
+        pass
+
     async def get_weather_for_city(self, city: str) -> CurrentWeather:
         """Convenience method: geocode and get current weather."""
         location = await self.geocode(city)
@@ -171,6 +260,15 @@ class WeatherProvider(ABC):
         return await self.get_current(location)
 
 
+class AirQualityProvider(ABC):
+    """Abstract base class for air quality API providers."""
+
+    @abstractmethod
+    async def get_air_quality(self, location: GeoLocation) -> AirQuality:
+        """Get current air quality for a location."""
+        pass
+
+
 class NewsProvider(ABC):
     """Abstract base class for news API providers."""