fix: enhance IP address validation to include global unicast check

[redscholar]

What type of PR is this?

/kind bug

What this PR does / why we need it:

etcd and kubelet need global or ula ip.

Which issue(s) this PR fixes:

Fixes #

Special notes for reviewers:

Does this PR introduced a user-facing change?

none

Additional documentation, usage docs, etc.:

[kubesphere-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: redscholar

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• OWNERS [redscholar]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[gemini-code-assist]

Code Review

This pull request refines the IP address selection logic in pkg/variable/variable_get.go by incorporating IsGlobalUnicast() checks for both IPv4 and IPv6 addresses. These changes ensure that only routable addresses are selected, filtering out link-local addresses that are unsuitable for cluster communication. I have no additional feedback to provide as the existing review comments were purely evaluative and did not identify any issues or further improvements.