Plan to release v3.6.6

[ivanvc]

What would you like to be added?

The etcd patch release criteria has been met for our release-3.6 stable branch, so we should release v3.6.6.

Work in progress CHANGELOG is: https://github.com/etcd-io/etcd/blob/main/CHANGELOG/CHANGELOG-3.6.md#v366-tba

The list of commits included since the previous release is: v3.6.5...release-3.6:

• [release-3.6] Reject watch request with -1 revision to prevent invalid resync behavior on uncompacted etcd and make rangeEvents safe against negative revision. #20707
• [release-3.6] server/embed: Log EOF on DEBUG in TLS handshake #20749
• [release-3.6] Fix endpoint status not retuning the correct storage quota #20790
• [release-3.6] Bump go to 1.24.9 #20801
• [release-3.6] etcdserver: Fix: cannot promote member from follower when auth is enabled #20874
• [release-3.6] Fix the issue that --force-new-cluster can't clean up learner after creating v2 snapshot #20896
• [release-3.6] Bump from go1.24.9 to go1.24.10 #20901
• [release-3.6] fix duplicate metrics collector registration attempted #20905

Outstanding tasks before releasing this version:

• None

Release team

GitHub handle	Role
@ivanvc	TBD

Why is this needed?

Regular patch releases are vital to ensure our users have bug-free and secure software.

[ivanvc]

Tentative release date: Monday, November 10th (KubeCon Monday).

[ivanvc]

We're planning on doing this release at KubeCon in the etcd kiosk on Tuesday, November 11th at 4:00 pm ET. We'll have @serathius and @siyuanfoundation there, so they can function as shadows. Also, inviting @upodroid for an initial exploration on automating our releases.

[ahrtr]

We need to bump etcd 3.6.6 on K8s. cc @joshjms @hakman @ivanvc

[yashsingh74]

@ahrtr I will work on it.

[ahrtr]

@ahrtr I will work on it.

thx, please follow https://github.com/etcd-io/etcd/blob/main/Documentation/contributor-guide/bump_etcd_version_k8s.md

ALso refer to #20936. We bump etcd 3.6.x to Kubernetes 1.34 and any new minor version (including master).

[ahrtr]

@yashsingh74 also FYI. @joshjms , @hakman @ivanvc and I all have experience on such work. Please raise your questions in slack channel sig-etcd or github comment (under your PR or this ticket) and cc the related experts.

[fuweid]

@ahrtr I am closing this. If we need to track dependency update in k8s side, we should create new issue for it.
Thanks @ivanvc for that release.

REF: kubernetes/kubernetes#135331

[ahrtr]

It isn't just only dependencies update. refer to https://github.com/etcd-io/etcd/blob/main/Documentation/contributor-guide/bump_etcd_version_k8s.md

Keeping the ticket open reflects sig-etcd own the task. It's also a good way to track the effort. It's easy to forget if we only raise issue in K8s repo. Note that @joshjms @hakman and I are the people who are most active doing such chores before, and we know the pains.