Expand /account_utxos with assets list and other related fields

[xray-robot]

Is your feature request related to a problem? Please describe.
There is no list of native tokens in the UTXO list

Describe the solution you'd like
Add optional _asset_list parameter to the /account_utxos endpoint to expand asset_list field

Example:

export type AccountUTXOs {
  tx_hash: string
  tx_index: number
  address: string
  value: string
  block_height: number | null
  block_time: number
  asset_list: { // expand this field if '_asset_list: true'
    policy_id: string
    asset_name: string | null
    fingerprint: string
    decimals: number
    quantity: string
  }[]
}

[xray-robot]

Perhaps we should add a full list of UTXO related fields, as in the /address_info endpoint:

[rdlrt]

Will be part of #186 , but need a proper release at dbsync before work starts here, as there will no longer be a requirement to track tx_in (for most part atleast)