imp: single service for all relayer modules

[srdtrk]

Description

closes: #224

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.84%. Comparing base (4edeb49) to head (1c7fee6).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #279   +/-   ##
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  Coverage   99.84%   99.84%           
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  Files          14       14           
  Lines         643      643           
=======================================
  Hits          642      642           
  Misses          1        1           

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[gjermundgaraba]

I think it mostly looks really good. 🚀 Thank you for pulling through so quickly on this 🙏
The only thing I want to change (which I will look at shortly) is the module serve function which doesn't make much sense anymore.

[gjermundgaraba]

I think this is a confusing artifact that doesn't really make sense anymore. I think a more reasonable approach might be simply let the modules not need to care about how the config gets to them, and instead just have the router that do this work and call new. I will look into this after I'm done with my current deployment work.