Reduce duplicate peer traffic for ledger data (#5126)

- Drop duplicate outgoing TMGetLedger messages per peer
  - Allow a retry after 30s in case of peer or network congestion.
  - Addresses RIPD-1870
  - (Changes levelization. That is not desirable, and will need to be fixed.)
- Drop duplicate incoming TMGetLedger messages per peer
  - Allow a retry after 15s in case of peer or network congestion.
  - The requestCookie is ignored when computing the hash, thus increasing
    the chances of detecting duplicate messages.
  - With duplicate messages, keep track of the different requestCookies
    (or lack of cookie). When work is finally done for a given request,
    send the response to all the peers that are waiting on the request,
    sending one message per peer, including all the cookies and
    a "directResponse" flag indicating the data is intended for the
    sender, too.
  - Addresses RIPD-1871
- Drop duplicate incoming TMLedgerData messages
  - Addresses RIPD-1869
- Improve logging related to ledger acquisition
- Class "CanProcess" to keep track of processing of distinct items

---------

Co-authored-by: Valentin Balaschenko <13349202+vlntb@users.noreply.github.com>

include/xrpl/basics/base_uint.h

@@ -631,6 +631,13 @@ to_string(base_uint<Bits, Tag> const& a)
     return strHex(a.cbegin(), a.cend());
 }
 
+template <std::size_t Bits, class Tag>
+inline std::string
+to_short_string(base_uint<Bits, Tag> const& a)
+{
+    return strHex(a.cbegin(), a.cend()).substr(0, 8) + "...";
+}
+
 template <std::size_t Bits, class Tag>
 inline std::ostream&
 operator<<(std::ostream& out, base_uint<Bits, Tag> const& u)