[Client] Allow to modify sensitivity of KeepAliveStopped

[romanett]

Proposed changes

Allow to modify sensitivity of KeepAliveStopped with a factor and a guard band.

Related Issues

• Fixes KeepAliveStopped m_keepAliveInterval factor has been removed in Session.cs  #2859

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• Enhancement (non-breaking change which adds functionality)
• Test enhancement (non-breaking change to increase test coverage)
• Breaking change (fix or feature that would cause existing functionality to not work as expected, requires version increase of Nuget packages)
• Documentation Update (if none of the other choices apply)

Checklist

• I have read the CONTRIBUTING doc.
• I have signed the CLA.
• I ran tests locally with my changes, all passed.
• I fixed all failing tests in the CI pipelines.
• I fixed all introduced issues with CodeQL and LGTM.
• I have added tests that prove my fix is effective or that my feature works and increased code coverage.
• I have added necessary documentation (if appropriate).
• Any dependent changes have been merged and published in downstream modules.

Further comments

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 57.47%. Comparing base (ac05ef6) to head (568a3c6).
Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3105      +/-   ##
==========================================
- Coverage   57.48%   57.47%   -0.02%     
==========================================
  Files         357      357              
  Lines       69113    69119       +6     
  Branches    14201    14203       +2     
==========================================
- Hits        39729    39723       -6     
- Misses      25136    25146      +10     
- Partials     4248     4250       +2     

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[mrsuciu]

Looks good

[Copilot]

Pull Request Overview

This PR enhances the KeepAliveStopped functionality by allowing configurable sensitivity through an interval factor and guard band, replacing the previously hardcoded values. This provides more flexibility for tuning keep-alive detection based on network conditions and application requirements.

• Replaces hardcoded guard band constant with configurable protected fields
• Modifies the KeepAliveStopped calculation to use a configurable factor and guard band
• Updates documentation to reflect the new configurable behavior

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
Libraries/Opc.Ua.Client/Session/Session.cs	Removes hardcoded constant, adds configurable fields for interval factor and guard band, updates KeepAliveStopped logic and documentation
Libraries/Opc.Ua.Client/Session/ISession.cs	Updates interface documentation to reflect configurable behavior