[CHERRY_PICK] fix(session): fix SessionRegenerate save args and lifetime

[chlins]

Thank you for contributing to Harbor!

Comprehensive Summary of your change

It's a cherry pick of #22873 and #22726.

This pull request makes improvements to session regeneration handling and enhances test coverage for session management. The main changes ensure that empty session data is stored with the correct type and add additional tests to verify session regeneration behavior.

Session regeneration improvements:

• Modified SessionRegenerate in session.go to store empty session data as a map instead of an empty string, ensuring correct session data type and consistency.

Session management test enhancements:

• Added new assertions in TestSessionRegenerate in session_test.go to test session regeneration for a new session ID (session-004), verifying that the session is properly created and exists after regeneration.

Issue being fixed

Fixes #(issue)

Please indicate you've done the following:

• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (release-2.14.0@87ea48a). Learn more about missing BASE report.

Additional details and impacted files

@@                Coverage Diff                @@
##             release-2.14.0   #22882   +/-   ##
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  Coverage                  ?   65.86%           
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  Files                     ?     1072           
  Lines                     ?   116078           
  Branches                  ?     2931           
=================================================
  Hits                      ?    76458           
  Misses                    ?    35384           
  Partials                  ?     4236           

Flag	Coverage Δ
unittests	65.86% <100.00%> (?)

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

Files with missing lines	Coverage Δ
src/core/session/session.go	37.60% <100.00%> (ø)

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[wy65701436]

lgtm

[MinerYang]

lgtm