Function fail

fail<T>(error: string): Decoder<T>
Decoder that always fails with the given error message.
Type Parameters
- T
Parameters
- error: string
  The error message to return
Returns Decoder<T>
A decoder that always fails with the specified error
Example
```
const failDecoder = JsonDecoder.fail<string>('This decoder always fails');
failDecoder.decode('anything'); // Err({error: 'This decoder always fails'})
```