Cardano Updates

A map is not necessary. All it causes is stm contention and
lifetime issues. A dedicated TVar drops when a connection is released,
and promotions and demotions won't clash when another connection's
muxer also wants to trace an activity.

This reverts commit b6d4137404f78d5169ddd4def118fe1408b95eb1.

This addresses the shrinker hang when attempting to shrink
'AbsBearerInfo' in some cases.

No other significant changes besides cosmetics.

This change fixes a termination bug in command shrinking and improves
the quality of shrinker results for the 'DiffusionScript'. The
overall perfomance should also improve with better pruning of nodes
and the commands which direct their execution.

o-n-framework shrinker improvement

Since the IG creates the connection handler by passing it
the new tracer, this argument was moved to the back of the list.
The prior arguments are created at the top level, where various
types are instantiated. This reflects the sequencing of applications
needed to create the CM.

This annotes each trace with a nice (node-x), where x is a number
[1..max-node in simulation]. This facilitates grepping a trace
for just the node that failed a test.

In the mkTracers binding, one can either turn on all component tracers
for general testing, and in case of failure of a test where only a
subset of components are really needed, one can selectively toggle
just the interesting sayTracers to further cut down the noise.

Comprehensibility improvements

The bug was exposed when Mux.run signature was changed to accept
the new MuxTracerBundle type instead of the Mux.Trace's Trace type.
The latter Trace type mixes low level bearer tags with the higher level
mux tags, so logically they are separate and in fact are traced by
separate components. The headerTracer must go along with the bearer tracer
otherwise it doesn't trace anything, but the types matched so the
program was accepted.

Contains mux tracer and separate channel tracer. The idea
is that the channel tracer should not contain the inbound
governor's information channel tracer which may be present
in the muxTracer field for certain connections. The protocol channel send/receive
trace tags are uniteresting from the IG tracer's perspective
but there is a penalty for invoking it so frequently for
every complete message.

The Server is started once the IG instantiates the CM with its tracer.

Some comments, and reordering/addition of tracing which
reflects functional perspective of how the IG processes
responder events and mux start/stop events.

Fix termination bug

The inbound governor information channel can reach its limit
when the server is shutting down and the IG loop stops draining it.
The mux async exception handler writes to the queue when each
connection is being torn down by the CM, which then awaits for
each handler to complete.

The tracer is attached to the inbound handler and to the outbound
handler only when a duplex mode was negotiated.

Also reflects changes to 'RemoteIdle' tag

Process all the info channel events from the queue in one step
of the IG loop. The queue events arrive from the CM (new connection)
or from the tracer which tracks miniprotocol responder activity
and mux start/stop.

The IG now applies the withConnectionManager continuation from the top
level Diffusion module to pass it the info channel tracer. Changes
in this module reflect the sequencing changes applied to the latter module.