Structural reorganization: watchdog taxonomy + server_reboot integration

Watchdog renames and moves:
  system_watchdog.sh → stability_watchdog.sh (last line of defense — reboots)
  storage_watchdog.sh → Watchdogs/System/storage_watchdog.sh
  webgui_restart.sh → Watchdogs/System/webgui_watchdog.sh (renamed to match folder convention)

New thin orchestrator:
  Watchdogs/system_watchdog.sh — runs SYSTEM_WATCHDOG_SCRIPTS from master.conf
  Sits between docker_watchdog and stability_watchdog in the orchestrator tier chain
  System/ subfolder is the growth seam for future system component watchdogs

master.conf:
  WATCHDOG_ORCHESTRATOR_SCRIPTS updated — storage removed, system_watchdog added as tier
  SYSTEM_WATCHDOG_SCRIPTS array added — storage + webgui

server_reboot.sh:
  Calls array_stopping.sh before VM shutdown for guaranteed safe array stop
  Removed raw rc.docker stop and exit trap — orchestrator owns container shutdown

Monitors/Manual-Monitors.md

@@ -232,7 +232,7 @@ data — it just doesn't trigger a notification for that condition.
 | `FALLBACK_STATE_FILE` | `Fallback/fallback.sh` | Current fallback state (NORMAL/FALLBACK/etc.) |
 | `SYS_WATCHDOG_FAILED_FILE` | `Watchdogs/docker_watchdog.sh` | Container skip list — needs human attention |
 | `WATCHDOG_STATE_FILE` | `Watchdogs/docker_watchdog.sh` | Active container strike counts |
-| `SYS_WATCHDOG_STATE_FILE` | `Watchdogs/system_watchdog.sh` | Active system watchdog strikes |
+| `SYS_WATCHDOG_STATE_FILE` | `Watchdogs/stability_watchdog.sh` | Active system watchdog strikes |
 | `BANDWIDTH_LOG` | `bandwidth_monitor.sh` | Yesterday's transfer history |
 | `TRANSCODE_DAILY_LOG` | `Transcodes/` | Weekly transcode statistics |
 | `CERT_MONITOR_DOMAINS` | live openssl check | Current cert status per domain |