Refactor communication module

[wonderplayer]

So, having Sockets in memory poses challenges in testing. Thus, extracted to separate module, so I can later on replace in-memory sockets with storing them in files to make them state-less. But definitely not right now, as will add additional file system complexity.

[codecov-commenter]

Codecov Report

Merging #113 (e96b77b) into main (694ec0f) will increase coverage by 0.18%. The diff coverage is 79.36%.

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@@           Coverage Diff            @@
##            main    #113      +/-   ##
========================================
+ Coverage   0.75%   0.93%   +0.18%     
========================================
  Files        130     131       +1     
  Lines       8722    8740      +18     
========================================
+ Hits          66      82      +16     
- Misses      8656    8658       +2     

Impacted Files	Coverage Δ
...sthaven_assistant/lib/services/network/client.dart	2.10% <0.00%> (ø)
...sthaven_assistant/lib/services/network/server.dart	0.00% <0.00%> (ø)
...thaven_assistant/lib/services/service_locator.dart	14.28% <0.00%> (-2.39%)	:arrow_down:
..._assistant/lib/services/network/communication.dart	83.33% <73.33%> (-10.15%)	:arrow_down:
...ven_assistant/lib/services/network/connection.dart	100.00% <100.00%> (ø)

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