Add DeployHQ to Tools (Git-driven deploys for non-Kubernetes targets)

[facundofarias]

Adds DeployHQ to ## Tools.

DeployHQ applies the GitOps principle — Git as the source of truth, push-to-deploy, full history and rollback — to deployment targets the existing entries don't cover: VPS and bare metal via SSH/SFTP, static sites to S3, and PaaS targets. Commits to GitHub, GitLab, or Bitbucket trigger declarative build-and-deploy pipelines with zero-downtime deploys and one-click rollback to any prior commit.

The list is Kubernetes-heavy by design, so this is explicitly the non-K8s case. If that's outside the list's intended scope, please close — I won't push back. The entry is slotted alphabetically between CloudBees Rollout and Flux.

• Project page: https://www.deployhq.com/

[o6uoq]

How does this adhere to the GitOps Principles? They are:

1. Declarative Systems
2. Versions and Immutable Desired State
3. Pulled Automatically
4. Continuously Reconciled