Add unit tests for pkg/daemon.go

[GautamBytes]

This PR adds unit tests for the errSignaler utility in pkg/daemon.

In Support of #2074

These tests cover the core error handling logic, including thread-safety, to ensure the daemon's lifecycle management is reliable.

Note: I initially planned to cover the entire package, but the NewDaemon function's use of a global client makes it difficult to mock. Rather than get blocked, this PR adds valuable, targeted tests for the self-contained errSignaler component as a good first step. We can tackle a refactor for broader test coverage in a follow-up.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 44.08%. Comparing base (f69813c) to head (7fb93d9).
⚠️ Report is 45 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2100      +/-   ##
==========================================
+ Coverage   43.99%   44.08%   +0.09%     
==========================================
  Files         316      316              
  Lines       31844    31844              
==========================================
+ Hits        14009    14040      +31     
+ Misses      16425    16394      -31     
  Partials     1410     1410              

Flag	Coverage Δ
unittests	44.08% <ø> (+0.09%)	⬆️

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[GautamBytes]

@furykerry can you rerun the workflow ? the 2 failing workflows seems unrelated to my changes!

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.