fix: simplify reboot to direct SSH invocation

STATE.md

@@ -48,7 +48,7 @@
 - `SSH_USER` is configurable and defaults to `root`
 - `NODES` parsing was hardened to preserve spaces in action values such as `cmd:...`
 - `cmd:<...>` is executed through a remote shell to support shell operators, but remains intentionally powerful and unsafe
-- `reboot` uses a detached remote command to reduce false failures caused by expected SSH disconnects
+- `reboot` now uses a direct SSH `reboot` invocation to keep the remote reboot path simple and predictable
 - `docker-stacks` runs through a remote shell script sent over SSH stdin to improve path handling and quoting
 - Startup dependency checks cover required local commands, including `mv` for log-summary rewriting
 
@@ -67,7 +67,7 @@
 - Log viewer fallback was made more flexible
 - `NODES` parsing was hardened to preserve spaces in action values
 - SSH execution was centralized and made configurable through `SSH_USER`
-- Remote command construction was improved for `pacman`, `docker-stacks`, and `reboot`
+- Remote command construction was improved for `pacman` and `docker-stacks`; `reboot` was simplified to a direct SSH command
 - Log summary generation was rewritten to avoid `sed -i` interpolation and now replaces the log atomically
 - `apk` and `apt` cleanup behavior was corrected to better match real package-manager semantics
 - The sample configuration in `config/netupgrade/hypervisor-01.cfg` now keeps the alternate `docker-01` reboot example commented out rather than active by default