Function maskBankAccount

maskBankAccount(input: unknown, visibleDigits?: number): string | null
Masks a valid bank account number after removing supported separators.
Parameters
- input: unknown
  Bank account number.
- visibleDigits: number = 4
  Digits to leave visible at the end. Defaults to 4.
Returns string | null
The masked account number, or null if invalid.
Example
```
maskBankAccount('1234-5678-90'); // '******7890'
```
- Defined in privacy/redaction.ts:83