Allow createWalletAddress mutation to take in additional properties

[mkurapov]

Context

During wallet address creation, we want to let the ASE allow to add additional properties to be associated with the wallet address.

We need to update the createWalletAddress mutation input to take in additionalProperties.
These properties would be optionally visible when requesting a wallet address through Open Payments. The input is an optional array of objects with key & value and visibleInOpenPayments (suggested name), a flag that enables or disables this field from appearing in Open Payments Wallet Address lookup.

Tasks

• Update createWalletAddress mutation input
• Store these fields in a new table with structure: walletAddressId: FK fieldKey: string fieldValue: string visibleInOpenPayments: bool, createdAt: Date, updatedAt: Date)
• Expose these new fields when fetching wallet address via Open Payments (making sure to show only fields that are indeed enabled for visibility for Open Payments)
• Expose these new fields when fetching wallet address via the Admin API
• Update the documentation

PR

#2752