upstream: feat(backend): implement proxy cache repository filter API (goharbor/harbor#23527)

[github-actions]

This cherry-pick had conflicts and was opened as a draft. Conflict markers may be present in the diff and must be resolved before marking ready for review.

Summary

Cherry-picks upstream Harbor commit 266aad1ec from goharbor/harbor#23527.

Upstream Context

• Upstream PR: feat(backend): implement proxy cache repository filter API goharbor/harbor#23527
• Upstream commit: 266aad1ecab9b08bf5c53c038439e36fbd50b7b7
• Upstream title: feat(backend): implement proxy cache repository filter API
• Upstream author: @stonezdj
• Upstream merged by: @stonezdj
• Upstream approved by: @chlins, @wy65701436
• Upstream PR URL: feat(backend): implement proxy cache repository filter API goharbor/harbor#23527
• Upstream commit URL: goharbor/harbor@266aad1

Cherry-Pick Status

• Status: conflicted
• Base branch: main
• Workflow run: https://github.com/container-registry/harbor-next/actions/runs/31196182666

Upstream Description

Introduce repository filter pattern and kind on proxy cache projects to explicitly allow selected repositories. Requests that do not match the filter are denied before Harbor proxies content from upstream.

Fixes #13231

Thank you for contributing to Harbor!

Comprehensive Summary of your change

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.

Review Notes

• Generated by the upstream cherry-pick workflow.
• One upstream commit maps to one Harbor Next PR.
• If this PR is closed without merge, the workflow will not recreate it.

Upstream-Commit: 266aad1ecab9b08bf5c53c038439e36fbd50b7b7
Upstream-PR: goharbor/harbor#23527
Cherry-Pick-Status: conflicted