Refactor the output component

[Molter73]

Description

This is a follow up to #2063.

This PR is focused on re-organizing the newly created CollectorOutput component into its own namespace. It is also grouped together with the sensor formatter, since they are tightly couple at the moment, but this might change in the near future.

A formal IClient interface is introduced and implementers of if are grouped into their own namespaces, this should make it easier to implement new output types by simply adding a new client in a separate namespace and implementing the interface. Right now the IClient interface only accounts for processes, but it will be extended in the near future to take a const std::variant& in order for it to also handle network information. This should also make it more flexible for adding newer message types in the future.

Checklist

• Investigated and inspected CI test results
• Updated documentation accordingly

Automated testing

• Added unit tests
• Added integration tests
• Added regression tests

If any of these don't apply, please comment below.

Testing Performed

TODO(replace-me)
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In addition to reviewing your code, reviewers must also review your testing instructions, and make sure they are sufficient.

For more details, ref the Confluence page about this section.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 33.33333% with 26 lines in your changes missing coverage. Please review.

Project coverage is 27.02%. Comparing base (ffbe42c) to head (8341cda).

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
collector/lib/output/Formatter.cpp	45.45%	6 Missing ⚠️
collector/lib/output/Output.cpp	33.33%	6 Missing ⚠️
collector/lib/output/grpc/Client.h	0.00%	6 Missing ⚠️
collector/lib/output/log/Client.h	0.00%	4 Missing ⚠️
collector/lib/output/grpc/Client.cpp	0.00%	3 Missing ⚠️
collector/lib/system-inspector/Service.cpp	0.00%	1 Missing ⚠️

Additional details and impacted files

@@                                 Coverage Diff                                 @@
##           mauro/ROX-28981-rework-collector-iservice-protobuf    #2086   +/-   ##
===================================================================================
  Coverage                                               27.02%   27.02%           
===================================================================================
  Files                                                      98      100    +2     
  Lines                                                    6046     6046           
  Branches                                                 2701     2701           
===================================================================================
  Hits                                                     1634     1634           
  Misses                                                   3693     3693           
  Partials                                                  719      719           

Flag	Coverage Δ
collector-unit-tests	27.02% <33.33%> (ø)

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