Refresh release docs for Docker Hub environments

docs/install.md

@@ -4,6 +4,7 @@
 
 - Linux x86_64 host
 - Python 3.12+
+- `uv`
 - `/dev/kvm`
 
 If you want outbound guest networking:
@@ -20,6 +21,12 @@ Run the MCP server directly from the package without a manual install:
 uvx --from pyro-mcp pyro mcp serve
 ```
 
+Prefetch the default official environment:
+
+```bash
+uvx --from pyro-mcp pyro env pull debian:12
+```
+
 Run one command in a curated environment:
 
 ```bash
@@ -38,6 +45,7 @@ uvx --from pyro-mcp pyro env list
 uv tool install pyro-mcp
 pyro --version
 pyro env list
+pyro env pull debian:12
 pyro env inspect debian:12
 pyro doctor
 ```