Add Google Artifact Registry adapter with OAuth2 authentication

[Strainy]

Comprehensive Summary of your change

This change adds a new adapter for Google Artifact Registry. We've been using Google ADC (via Workload Identity Federation) in combination with this adapter for a number of months. All working well.

Issue being fixed

Fixes #20682

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.
✅ Project coverage is 46.67%. Comparing base (c8c11b4) to head (a86f7c3).
⚠️ Report is 573 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #22429      +/-   ##
==========================================
+ Coverage   45.36%   46.67%   +1.30%     
==========================================
  Files         244      252       +8     
  Lines       13333    14255     +922     
  Branches     2719     2927     +208     
==========================================
+ Hits         6049     6653     +604     
- Misses       6983     7246     +263     
- Partials      301      356      +55     

Flag	Coverage Δ
unittests	46.67% <ø> (+1.30%)	⬆️

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

Files with missing lines	Coverage Δ
...rojects/create-project/create-project.component.ts	49.64% <ø> (-0.78%)	⬇️
...t-policy-config/project-policy-config.component.ts	52.65% <ø> (+3.90%)	⬆️

... and 176 files with indirect coverage changes

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[Vad1mo]

This is a needed addition...

[Copilot]

Pull Request Overview

This PR adds Google Artifact Registry (GAR) adapter with OAuth2 authentication support to Harbor's registry replication system. The adapter extends Harbor's capability to proxy/replicate from Google's newer GAR service alongside the existing GCR support.

• Implements OAuth2 authentication for Google Artifact Registry
• Adds comprehensive adapter implementation with proper endpoint patterns
• Updates UI and configuration to include GAR in supported registry types

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/portal/src/i18n/lang/en-us-lang.json	Updates tooltip text to include Google GAR in supported proxy cache registries
src/portal/src/app/base/project/project-config/project-policy-config/project-policy-config.component.ts	Adds google-gar to supported registry type query string
src/portal/src/app/base/left-side-nav/projects/create-project/create-project.component.ts	Adds google-gar to supported registry type query string
src/pkg/reg/model/registry.go	Defines RegistryTypeGoogleGar constant
src/pkg/reg/manager.go	Registers the Google GAR adapter import
src/pkg/reg/adapter/googlegar/auth/*	Implements OAuth2 authentication with comprehensive test coverage
src/pkg/reg/adapter/googlegar/adapter*	Core GAR adapter implementation with registry pattern definitions
src/pkg/chart/testdata/harbor-schema*/templates/core/core-cm.yaml	Updates permitted registry types to include google-gar
src/jobservice/job/impl/replication/replication.go	Imports the googlegar adapter for job service usage

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[stonezdj]

Thanks for your contribution, could you please demo this adapter in our community meeting? if you could add a CI to verify the GAR adapter would be appreciated.

[Strainy]

Thanks for your contribution, could you please demo this adapter in our community meeting?

I'm quite pressed for time at the moment, so won't be able to do this.

if you could add a CI to verify the GAR adapter would be appreciated.

I've added unit tests. Is there something else I need to do to "add a CI"? Maybe an example is in order 🙏