feat: add secret/service resource checker for webhook

[ronething]

Type of change:

• Bugfix
• New feature provided
• Improve performance
• Backport patches
• Documentation
• Refactor
• Chore
• CI/CD or Tests

What this PR does / why we need it:

This PR adds more webhook validations. The resources for adding validations are HTTPRoute, GRPCRoute, TCPRoute, Gateway, and Ingress.

This PR has also added corresponding unit tests, while e2e tests have not been supplemented yet.

ref: #2580

Pre-submission checklist:

• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

[Copilot]

Pull Request Overview

This PR adds webhook validation for secret and service resource references in HTTPRoute, GRPCRoute, TCPRoute, Gateway, and Ingress resources. The validation helps catch misconfigurations by warning users when referenced resources (Services/Secrets) don't exist in the cluster.

Key changes implemented:

• Webhook validators for Gateway API resources (HTTPRoute, GRPCRoute, TCPRoute) that check service references
• Enhanced Ingress webhook validator to check both service and secret references
• Enhanced Gateway webhook validator to check TLS certificate secret references
• Ownership checking logic to determine if resources are managed by the APISIX controller

Reviewed Changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
internal/webhook/v1/httproute_webhook.go	New HTTPRoute webhook validator with service reference checking
internal/webhook/v1/grpcroute_webhook.go	New GRPCRoute webhook validator with service reference checking
internal/webhook/v1/tcproute_webhook.go	New TCPRoute webhook validator with service reference checking
internal/webhook/v1/gateway_webhook.go	Enhanced Gateway validator with TLS secret reference checking
internal/webhook/v1/ingress_webhook.go	Enhanced Ingress validator with service/secret reference checking
internal/webhook/v1/ownership.go	New ownership checking logic for Gateway API resources
internal/manager/webhooks.go	Registration of new webhook validators
config/webhook/manifests.yaml	Webhook configuration manifests

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[Revolyssup]

Since UDPRoute PR is merged. Should we add that as well?

[ronething]

Yes, but i think we can handle it in the next PR. This PR is getting more and more inflated.