[node-split] Add command for starting services

[jellonek]

Closes #6618

Note

This PR is not yet removing the old method of starting the node. It should probably be replaced with "combined" mode if we want to keep it as a transition way to new approach.

Also parameters configuration is kept untouched so in activation service mode code is expecting that user will provide --node-service-address while in node service mode the code is expecting that this variable would be NOT set.

[pigmej]

This needs to be added to the changelog.md ;)

[jellonek]

CHANGELOG.md updated.

[codecov]

Codecov Report

Attention: Patch coverage is 45.42683% with 537 lines in your changes missing coverage. Please review.

Please upload report for BASE (node-split-poc@837e7fa). Learn more about missing BASE report.
Report is 15 commits behind head on node-split-poc.

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
node/smeshing_service.go	0.0%	484 Missing ⚠️
node/node.go	89.4%	44 Missing and 9 partials ⚠️

Additional details and impacted files

@@               Coverage Diff                @@
##             node-split-poc   #6625   +/-   ##
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  Coverage                  ?   77.1%           
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  Files                     ?     377           
  Lines                     ?   51830           
  Branches                  ?       0           
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  Hits                      ?   40011           
  Misses                    ?    9451           
  Partials                  ?    2368           

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[poszu]

It's a great start!

Next thing I'd imagine removing all smeshing-related stuff which is not needed on the node-service from the node_service.go (like atx builder, POST initialization etc.).