feat: update DiscoveryMessage struct and add API documentation

internal/handler/discovery.go

@@ -9,8 +9,8 @@ import (
 
 // DiscoveryMessage represents the JSON payload from a device discovery message
 type DiscoveryMessage struct {
-	MACAddress string                 `json:"mac_address"`
-	Device     DiscoveryDevicePayload `json:"device"`
+	MACAddress string                   `json:"mac_address"`
+	Device     DiscoveryDevicePayload   `json:"device"`
 	Sensors    []DiscoverySensorPayload `json:"sensors"`
 	Actors     []DiscoveryActorPayload  `json:"actors"`
 }
@@ -162,7 +162,7 @@ func (h *Handler) updateExistingDevice(msg DiscoveryMessage, previousStatusID in
 	return nil
 }
 
-// getDeviceSensors retrieves existing sensors for a device
+// getDeviceSensors retrieves existing sensors for a device<
 func getDeviceSensors(tx *sql.Tx, deviceID string) (map[string]DiscoverySensorPayload, error) {
 	rows, err := tx.Query(
 		"SELECT BIN_TO_UUID(id), name, type, data_type_id FROM sensors WHERE device_id = UUID_TO_BIN(?) ORDER BY id",