feat(arbiter-core / arbiter-engine): broadcasters, halting, test sims

[Autoparallel]

Give an overview of the tasks completed
Managed to switch over to using tokio::sync::broadcast as the broadcaster of choice in both arbiter-core and arbiter-agent which seemed to fix concurrency issues with agent behaviors. This gets both the issues below.

Link to issue(s) that this PR closes

• Closes feat(arbiter-engine): World driving Agent behaviors concurrently #788
• Closes enhance(arbiter-core): use a broadcast (like tokio::sync or async-broadcast) in Environment.Socket #756

** IN PROGRESS**
World::stop() is broken, however agents can halt their behavior processing by choice in definition of that behavior.
Replaced with #802

[0xJepsen]

I'm into merging this. Nice work fighting this battle with the async demons

[codecov]

Codecov Report

Attention: 53 lines in your changes are missing coverage. Please review.

Comparison is base (7ecc57a) 53.29% compared to head (a6744b8) 56.48%.
Report is 47 commits behind head on main.

Files	Patch %	Lines
arbiter-engine/src/agent.rs	89.72%	15 Missing ⚠️
arbiter-engine/src/machine.rs	76.36%	13 Missing ⚠️
arbiter-engine/src/world.rs	85.39%	13 Missing ⚠️
arbiter-core/src/middleware/connection.rs	85.29%	5 Missing ⚠️
arbiter-core/src/data_collection.rs	95.12%	2 Missing ⚠️
arbiter-core/src/environment/mod.rs	81.81%	2 Missing ⚠️
arbiter-engine/src/messager.rs	94.28%	2 Missing ⚠️
arbiter-core/src/middleware/mod.rs	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #801      +/-   ##
==========================================
+ Coverage   53.29%   56.48%   +3.19%     
==========================================
  Files          37       38       +1     
  Lines        7397     7637     +240     
==========================================
+ Hits         3942     4314     +372     
+ Misses       3455     3323     -132     

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