fix: preserve battery array encoding with json v2

internal/entities/system/system_test.go

@@ -2,6 +2,7 @@ package system
 
 import (
 	"encoding/json"
+	jsonv2 "encoding/json/v2"
 	"testing"
 
 	"github.com/fxamacker/cbor/v2"
@@ -12,12 +13,19 @@ import (
 func TestStatsBatteryTransport(t *testing.T) {
 	stats := Stats{Battery: [2]uint8{0, 1}, Batteries: map[string]uint8{"Primary": 0, "Mouse": 75}}
 
-	jsonData, err := json.Marshal(stats)
-	require.NoError(t, err)
-	var jsonPayload map[string]any
-	require.NoError(t, json.Unmarshal(jsonData, &jsonPayload))
-	assert.Equal(t, []any{float64(0), float64(1)}, jsonPayload["bat"])
-	assert.Equal(t, map[string]any{"Primary": float64(0), "Mouse": float64(75)}, jsonPayload["bats"])
+	for name, marshal := range map[string]func(any) ([]byte, error){
+		"json_v1": json.Marshal,
+		"json_v2": func(value any) ([]byte, error) { return jsonv2.Marshal(value) },
+	} {
+		t.Run(name, func(t *testing.T) {
+			jsonData, err := marshal(stats)
+			require.NoError(t, err)
+			var jsonPayload map[string]any
+			require.NoError(t, json.Unmarshal(jsonData, &jsonPayload))
+			assert.Equal(t, []any{float64(0), float64(1)}, jsonPayload["bat"])
+			assert.Equal(t, map[string]any{"Primary": float64(0), "Mouse": float64(75)}, jsonPayload["bats"])
+		})
+	}
 
 	cborData, err := cbor.Marshal(stats)
 	require.NoError(t, err)
@@ -27,6 +35,12 @@ func TestStatsBatteryTransport(t *testing.T) {
 	assert.Equal(t, stats.Batteries, decoded.Batteries)
 }
 
+func TestStatsBatteryNumericArrayUnmarshal(t *testing.T) {
+	var stats Stats
+	require.NoError(t, json.Unmarshal([]byte(`{"bat":[50,4]}`), &stats))
+	assert.Equal(t, Battery{50, 4}, stats.Battery)
+}
+
 func TestStatsLegacyBatteryPayload(t *testing.T) {
 	data, err := json.Marshal(Stats{Battery: [2]uint8{50, 4}})
 	require.NoError(t, err)