feat: auto-recreate sandbox containers on config change

docs/install/docker.md

@@ -254,6 +254,14 @@ precedence, and troubleshooting.
 
 ### Enable sandboxing
 
+If you plan to install packages in `setupCommand`, note:
+- Default `docker.network` is `"none"` (no egress).
+- `readOnlyRoot: true` blocks package installs.
+- `user` must be root for `apt-get` (omit `user` or set `user: "0:0"`).
+Clawdbot auto-recreates containers when `setupCommand` (or docker config) changes
+unless the container was **recently used** (within ~5 minutes). Hot containers
+log a warning with the exact `clawdbot sandbox recreate ...` command.
+
 ```json5
 {
   agents: {