`fetchUrl` throws generic error, discarding specific error details from response

[0xpatrickdev]

When using @chain-registry/client via starshipjs, I observed a generic Bad response error and had trouble tracking down the root cause of an issue.

I came to learn the starship registry service returned a helpful error message:

{"code":2, "message":"not found: no ibc connection found between chainA and chainB", "details":[]}

But it was swallowed by the client:
https://github.com/cosmology-tech/chain-registry/blob/b3b39185825b46807816e07d427935c56938923a/v1/packages/client/src/fetcher.ts#L13-L20

https://github.com/cosmology-tech/chain-registry/blob/b3b39185825b46807816e07d427935c56938923a/v2/packages/client/src/fetcher.ts#L26-L33

Changes along these lines should surface reported errors:

const fetchUrl = async (url: string) => {
  const res = await fetch(url);
  const data = await res.json();

  if (!res.ok) {
    // If the response contains error information, use it
    if (data && data.code !== undefined && data.message) {
      const error = new Error(data.message) as Error & {
        code?: number;
        details?: any[];
      };
      error.code = data.code;
      error.details = data.details;
      throw error;
    } else {
      throw new Error(`Bad Response: ${res.status}`);
    }
  }

  return data;
};