Allow fetch functions to pass headers

[45930]

Whenever an http request is made by o1js, we should allow developers to pass headers to the server. In particular, we should expose two new functions in the fetch module: setMinaDefaultHeaders and setArchiveDefaultHeaders, which add the configured headers to every request, and update the function signature for the methods that make a request one time (fetchAccount, fetchEvents, fetchActions, etc...).

This feature will enable developers to run private archive nodes or Mina nodes requiring a key, requests to pools of nodes to submit a series of requests to the same exact node, and other features like these on the node operator side.

[kadirchan]

Hi @45930 I sent a PR (#2004)for this issue. Please let me know if there is any missing part.