curl --request GET \
  --url https://{host}/extern/svr/{accountTypeId}/account/{accountId}/balance \
  --header 'X-API-Key: <api-key>'

{
  "status": "<string>",
  "data": {
    "accountId": "<string>",
    "safeAddress": "<string>",
    "perChain": [
      {
        "chainId": 123,
        "vaultAddress": "<string>",
        "total": {},
        "totalUnderlying": "<string>",
        "totalUnderlyingDecimals": 123,
        "heldAssets": [
          {
            "address": "<string>",
            "symbol": "<string>",
            "chainId": 123
          }
        ]
      }
    ],
    "total": {},
    "heldAssets": [
      {
        "address": "<string>",
        "symbol": "<string>",
        "chainId": 123
      }
    ]
  }
}