Add CNI cilium configuration

[xunholy]

Description

Configure Cilium configuration to replace calico using the existing podCIDR and relevant config.

Fixed:

• workflows for automating flux and pre-commit hooks
• peer authentication namespace scope

Checklist

• All commits are signed off. See the section Developer’s Certificate of Origin
• Provide a title or release-note blurb suitable for the release notes.
• All pre-commit hook validation passed successfully.
• All commits contain a well-written commit description including a title, description, and a Fixes: #XXX line if the commit addresses a particular GitHub issue.
• All workflow validation and compliance checks are passing.

Issue Ref (Optional)

Which issue(s) this PR fixes (optional, using fixes #(, fixes #<issue_number>, ...) format, will close the issue(s) when the PR gets merged): #96

Notes

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