Docs(Docker): clarify official GHCR image guidance

docs/install/docker.md

@@ -94,6 +94,19 @@ Running on a VPS? See [Hetzner (Docker VPS)](/install/hetzner).
 
 ### Use a remote image (skip local build)
 
+Official pre-built images are published at:
+
+- [GitHub Container Registry package](https://github.com/openclaw/openclaw/pkgs/container/openclaw)
+
+Use image name `ghcr.io/openclaw/openclaw` (not similarly named Docker Hub
+images).
+
+Common tags:
+
+- `main` — latest build from `main`
+- `<version>` — release tag builds (for example `2026.2.26`)
+- `latest` — latest stable release tag
+
 By default the setup script builds the image from source. To pull a pre-built
 image instead, set `OPENCLAW_IMAGE` before running the script:
 
@@ -106,8 +119,9 @@ The script detects that `OPENCLAW_IMAGE` is not the default `openclaw:local` and
 runs `docker pull` instead of `docker build`. Everything else (onboarding,
 gateway start, token generation) works the same way.
 
-This is useful when you want to skip cloning the repo or avoid a local build
-entirely.
+`docker-setup.sh` still runs from the repository root because it uses the local
+`docker-compose.yml` and helper files. `OPENCLAW_IMAGE` skips local image build
+time; it does not replace the compose/setup workflow.
 
 ### Shell Helpers (optional)