Add support to specify constraints macros inline for submodels

[ofSingularMind]

Simple patch :)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.58%. Comparing base (6c2c094) to head (bcb9295).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #302      +/-   ##
==========================================
+ Coverage   90.56%   90.58%   +0.02%     
==========================================
  Files          16       16              
  Lines        2184     2189       +5     
==========================================
+ Hits         1978     1983       +5     
  Misses        206      206              

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[bvdmitri]

both this one and ReactiveBayes/RxInfer.jl#653 should update the documentation and explain how to use this feature with examples

[bvdmitri]

E.g. we have syntax which is documented

@constraints begin 
      for q in submodel 
         ...
      end
end

is that not enough for your use case?