feature: Add conversion to AQI index from value

app/src/main/java/com/warbler/data/model/weather/AQI.kt

@@ -0,0 +1,73 @@
+package com.warbler.data.model.weather
+
+enum class AQI {
+    GOOD,
+    FAIR,
+    MODERATE,
+    POOR,
+    VERY_POOR,
+    INVALID
+}
+
+fun getSo2Index(value: Int): AQI = when {
+    value < 20 -> AQI.GOOD
+    value in 21..80 -> AQI.FAIR
+    value in 81..250 -> AQI.MODERATE
+    value in 251..350 -> AQI.POOR
+    value > 350 -> AQI.VERY_POOR
+    else -> AQI.INVALID
+}
+
+fun getNo2Index(value: Int): AQI = when {
+    value < 40 -> AQI.GOOD
+    value in 41..70 -> AQI.FAIR
+    value in 71..150 -> AQI.MODERATE
+    value in 151..200 -> AQI.POOR
+    value > 200 -> AQI.VERY_POOR
+    else -> AQI.INVALID
+}
+
+
+fun getPm10Index(value: Int): AQI = when {
+    value < 20 -> AQI.GOOD
+    value in 21..50 -> AQI.FAIR
+    value in 51..100 -> AQI.MODERATE
+    value in 101..200 -> AQI.POOR
+    value > 201 -> AQI.VERY_POOR
+    else -> AQI.INVALID
+}
+
+
+fun getPm25Index(value: Int): AQI = when {
+    value < 10 -> AQI.GOOD
+    value in 11..25 -> AQI.FAIR
+    value in 26..50 -> AQI.MODERATE
+    value in 51..75 -> AQI.POOR
+    value > 76 -> AQI.VERY_POOR
+    else -> AQI.INVALID
+}
+
+
+fun getO3Index(value: Int): AQI = when {
+    value < 60 -> AQI.GOOD
+    value in 61..100 -> AQI.FAIR
+    value in 101..140 -> AQI.MODERATE
+    value in 141..180 -> AQI.POOR
+    value > 181 -> AQI.VERY_POOR
+    else -> AQI.INVALID
+}
+
+
+fun getC0Index(value: Int): AQI = when {
+    value < 4400 -> AQI.GOOD
+    value in 4401..9400 -> AQI.FAIR
+    value in 9401..12400 -> AQI.MODERATE
+    value in 12401..15400 -> AQI.POOR
+    value > 15401 -> AQI.VERY_POOR
+    else -> AQI.INVALID
+}
+
+
+fun getNh3Index(value: Int): AQI = AQI.INVALID
+
+fun getNoIndex(value: Int): AQI = AQI.INVALID