feat: added exit codes for CLI daemon command errors

[cmaglie]

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• Tests for the changes have been added (for bug fixes / features)
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• configuration.schema.json updated if new parameters are added.

What kind of change does this PR introduce?

Makes the daemon command return a consistent exit code for specific errors.

What is the current behavior?

The exit code was a bit random:

• If "CLI failed to open a TCP port to listen for incoming connections" the exit code could be 1 (Generic error), 5 (Network error), or 0 (Success!)
• If "TCP port argument is not valid" the exit code could be 6 (Core config error) or 7 (Bad Argument error).

What is the new behavior?

The following error codes have been added:

• code 8: CLI failed to open a TCP port to listen for incoming connections
• code 9: TCP port argument is not valid

Does this PR introduce a breaking change, and is titled accordingly?

Other information

Related to #2352

[codecov]

Codecov Report

Attention: 8 lines in your changes are missing coverage. Please review.

Comparison is base (cc3396f) 64.58% compared to head (5874dec) 64.61%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2400      +/-   ##
==========================================
+ Coverage   64.58%   64.61%   +0.03%     
==========================================
  Files         207      207              
  Lines       19634    19634              
==========================================
+ Hits        12681    12687       +6     
+ Misses       5863     5859       -4     
+ Partials     1090     1088       -2     

Flag	Coverage Δ
unit	64.61% <0.00%> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
internal/cli/daemon/daemon.go	48.51% <0.00%> (ø)

... and 1 file with indirect coverage changes

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