Fix body battery array parsing - use index 1 not 2

The Garmin API returns bodyBatteryValuesArray as [timestamp, level]
tuples (2 elements), not [timestamp, status, level, quality] (4 elements).
Was accessing index 2 which doesn't exist, now correctly using index 1.

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

src/lib/garmin.test.ts

@@ -342,9 +342,9 @@ describe("fetchBodyBattery", () => {
           charged: 45,
           drained: 30,
           bodyBatteryValuesArray: [
-            [1705190400000, "charging", 25, 1.0],
-            [1705194000000, "draining", 40, 1.0],
-            [1705197600000, "charging", 35, 1.0],
+            [1705190400000, 25],
+            [1705194000000, 40],
+            [1705197600000, 35],
           ],
         },
         {
@@ -352,8 +352,8 @@ describe("fetchBodyBattery", () => {
           charged: 85,
           drained: 60,
           bodyBatteryValuesArray: [
-            [1705276800000, "charging", 65, 1.0],
-            [1705280400000, "draining", 85, 1.0],
+            [1705276800000, 65],
+            [1705280400000, 85],
           ],
         },
       ]),
@@ -432,7 +432,7 @@ describe("fetchBodyBattery", () => {
       mockJsonResponse([
         {
           date: "2024-01-15",
-          bodyBatteryValuesArray: [[1705276800000, "charging", 70, 1.0]],
+          bodyBatteryValuesArray: [[1705276800000, 70]],
         },
       ]),
     );

src/lib/garmin.ts

@@ -137,31 +137,27 @@ export async function fetchBodyBattery(
       );
       return { current: null, yesterdayLow: null };
     }
+    // Response structure: bodyBatteryValuesArray is [[timestamp, level], ...]
+    // Confirmed by bodyBatteryValueDescriptorDTOList in API response
     const data = JSON.parse(text) as Array<{
       date: string;
-      bodyBatteryValuesArray?: Array<[number, string, number, number]>;
+      bodyBatteryValuesArray?: Array<[number, number]>;
     }>;
 
-    // Debug: log the raw response structure
-    logger.info(
-      { rawData: JSON.stringify(data).slice(0, 2000), date, yesterday },
-      "Body battery raw API response",
-    );
-
     // Find today's and yesterday's data from the response array
     const todayData = data?.find((d) => d.date === date);
     const yesterdayData = data?.find((d) => d.date === yesterday);
 
-    // Current = last value in today's bodyBatteryValuesArray (index 2 is the level)
+    // Current = last value in today's bodyBatteryValuesArray (index 1 is the level)
     const todayValues = todayData?.bodyBatteryValuesArray ?? [];
     const current =
-      todayValues.length > 0 ? todayValues[todayValues.length - 1][2] : null;
+      todayValues.length > 0 ? todayValues[todayValues.length - 1][1] : null;
 
     // Yesterday low = minimum level in yesterday's bodyBatteryValuesArray
     const yesterdayValues = yesterdayData?.bodyBatteryValuesArray ?? [];
     const yesterdayLow =
       yesterdayValues.length > 0
-        ? Math.min(...yesterdayValues.map((v) => v[2]))
+        ? Math.min(...yesterdayValues.map((v) => v[1]))
         : null;
 
     logger.info(