chore: drop the openhands service

Remove the directory and its row from the root table, the related-services link
in opencode-web, and the workspace-volume convention's reference to it.

README.md

@@ -59,7 +59,6 @@ Each links to its own README for variables, ports, and storage.
 | [diun](diun/README.md) | Image-update notifier, reading the Docker API through a read-only proxy |
 | [gitea-mirror](gitea-mirror/README.md) | Gitea + PostgreSQL + gitea-mirror, mirroring GitHub repos |
 | [opencode-web](opencode-web/README.md) | opencode coding agent, served as a browser UI |
-| [openhands](openhands/README.md) | OpenHands coding agent, running each session in a container it spawns |
 | [paseo](paseo/README.md) | Paseo coding-agent daemon and web UI |
 | [traffmonetizer](traffmonetizer/README.md) | TraffMonetizer bandwidth-sharing client |