FUNCT the call handler reports calls to history

We cannot report the function name yet, so it is undefined in the tests

We also create a component test to check the interactions between the call
handler and the history server
FUNCT better type specs
FUNCT add the history server to the moka server state

So that moka server can instruct the call handlers to report history to the
appropriate history server
FUNCT better type specs
TEST The call handler needs a reference to a history server to start

For the unit tests it is irrelevant, calls are asynchronous and they cannot
fail, even if the history server doesn't exist, so we just pass an arbitrary
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