Don't hardcode `localhost` in `did:web` resolver as callback address

scitt-ccf-ledger/app/src/did/web/method.h

Lines 53 to 55 in 28a7820

    
           auto [_host, port] = 
        
             ccf::split_net_address(primary_interface.bind_address); 
        
           return fmt::format("https://localhost:{}/did/{}/doc", port, did);

If a node is configured to bind to 0.0.0.0 then using localhost works. But if it binds to a concrete IP address that's not 0.0.0.0, then localhost doesn't work.

The code should be changed to just use the binding address as callback address as-is. Note that this works even with 0.0.0.0 (which is mostly a Linux feature).

	auto [_host, port] =
	ccf::split_net_address(primary_interface.bind_address);
	return fmt::format("https://localhost:{}/did/{}/doc", port, did);