dealing with types and internal modules like `~bank`

[pyramation]

We can create a declaration file (e.g., bank.d.ts) to declare the types for internal packages:

declare module '~bank' {
  export function getBalance(): number;
  export function sendCoins(amount: number): void;
}

[Anmol1696]

Should this be part of hyperbweb-build? something like: @hyperweb/types?