Publish release v1.16.0

[zhzhuang-zju]

What would you like to be added:
According to Karmada's release cycle, the release team is preparing to release v1.16.0 the end of the month(2025-11-29), along with patch versions for the maintenance releases. This issue is to submit the release publishing tasks.

karmada repo:

• prepare release notes (@zhzhuang-zju pulish release v1.16.0,v1.15.3,v1.14.7,v1.13.10 #6962 )

• release the v1.16.0, v1.15.3, v1.14.7, v1.13.10 (@RainbowMango )

• Stop maintaining version 1.13 and maintain version 1.16 (@zhzhuang-zju CI: Stop maintaining version 1.13 and maintain version 1.16 #6993)

  • update ci-schedule-compatibility.yaml
    URL: https://github.com/karmada-io/karmada/blob/master/.github/workflows/ci-schedule-compatibility.yaml
  • update dependabot.yaml
    URL: https://github.com/karmada-io/karmada/blob/master/.github/dependabot.yml
  • update ci-image-scanning-on-schedule.yml
    URL: https://github.com/karmada-io/karmada/blob/master/.github/workflows/ci-image-scanning-on-schedule.yml

• Update sample file of Karmada operator

  • Update imageTag of Karmada components from v1.15.0 to v1.16.0 (@zhzhuang-zju update karmada-sample.yaml #6988 )

• Add helm index v1.16.0 (@zhzhuang-zju add helm index v1.16.0 #6990)

• Update Kubernetes compatibility (@zhzhuang-zju CI: Stop maintaining version 1.13 and maintain version 1.16 #6993)

website repo:

• Update Reference Documents(reference: https://karmada.io/docs/developers/document-releasing#update-reference-documentsmanually) (@zhzhuang-zju add reference docs website#939)
• Add upgrading v1.15 to v1.16 docs (@zhzhuang-zju add upgrading docs from v1.15 to v1.16 website#938)
• Release docs for release-1.16 (@zhzhuang-zju release release-1.16 docs website#940)
• Stop maintaining v1.10 (@zhzhuang-zju stop maintaining release 1.10 docs website#941)
• release branch release-1.16 (@RainbowMango )

Why is this needed:

[zhzhuang-zju]

/help

[karmada-bot]

@zhzhuang-zju:
This request has been marked as needing help from a contributor.

Please ensure the request meets the requirements listed here.

If this request no longer meets these requirements, the label can be removed
by commenting with the /remove-help command.

In response to this:

/help

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[zhzhuang-zju]

@RainbowMango Now we can release branch release-1.16 in the website repo

[RainbowMango]

Done.
https://github.com/karmada-io/website/tree/release-1.16

[zhzhuang-zju]

Perfect! Once #6993 and #6988 are merged, all the release publish tasks will be done