[consensus/marshal] specific reporters type to send to multiple consumers

[SuperFluffy]

This patch provides a marshal-specific Reporters type to allow sending the Update<B> enum to more than one consumer.

#2144 enshrined finalizer await by including a oneshot channel in the marshal::Update<B> enum, which is a good change. However, it broke the consensus::Reporter for Reporters<R1, R2> impl by requiring that the Activity: Clone.

monorepo/consensus/src/reporter.rs

Lines 31 to 36 in fe0dcf4

	impl<A, R1, R2> Reporter for Reporters<A, R1, R2>
	where
	A: Clone + Send + 'static,
	R1: Reporter<Activity = A>,
	R2: Reporter<Activity = A>,
	{

.

This was likely not caught because no commonware example uses consensus::Reporters in the marshal agent.

[clabby]

Looks good. Mind adding a short test for 2 & 3 reporters (the latter nesting the new struct: Reporters<A, Reporter, Reporters<A, Reporter, Reporter>>)?

[SuperFluffy]

Looks good. Mind adding a short test for 2 & 3 reporters (the latter nesting the new struct: Reporters<A, Reporter, Reporters<A, Reporter, Reporter>>)?

Added some very simple tests checking receipt of acks and blocks.

[clabby]

note - We already have the assumption that application is a cheap clone (either a mailbox or a shallow struct for Marshaled.) This should be low-cost.

[codecov]

Codecov Report

❌ Patch coverage is 93.29897% with 13 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.21%. Comparing base (fe0dcf4) to head (bd925c9).
⚠️ Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
consensus/src/marshal/mod.rs	91.72%	12 Missing ⚠️
consensus/src/marshal/actor.rs	97.95%	1 Missing ⚠️

@@            Coverage Diff             @@
##             main    #2202      +/-   ##
==========================================
- Coverage   92.22%   92.21%   -0.01%     
==========================================
  Files         315      314       -1     
  Lines       86561    86557       -4     
==========================================
- Hits        79827    79822       -5     
- Misses       6734     6735       +1     

Files with missing lines	Coverage Δ
consensus/src/marshal/actor.rs	87.98% <97.95%> (+0.46%)	⬆️
consensus/src/marshal/mod.rs	97.82% <91.72%> (-1.39%)	⬇️

... and 30 files with indirect coverage changes

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[patrick-ogrady]

I considered making a new type for this to avoid a custom reporter but it becomes very difficult to actually know when it is safe to "listen" on this type (as one actor may finish before the "sender" is cloned).

It seems we need to be explicit in the number of recipients to ensure we properly wait for everything.

[patrick-ogrady]

forgot about this lol...fml

[patrick-ogrady]

This second clone is unnecessary (pushed a fix)

[patrick-ogrady]

I don't like that we call report in async here but not for tip. It implies a very specific function of report() that to me indicates of a deeper issue.