Bring script headers onto the template and close safeguard gaps

Headers claimed protections the code never had, and several destructive paths had no
guard against a collapsed config value.

Tools/watchdog_skip_list_manager.sh

@@ -28,6 +28,45 @@
 #   4. Watchdog monitors normally on next cycle. If it crashes again → re-added.
 #
 # ==============================================================================================
+# DESIGN PRINCIPLES
+# ==============================================================================================
+#
+# Clearing Is an Assertion, Not a Fix
+#   Removing a container from the skip list tells docker_watchdog.sh to start restarting
+#   it again. It does nothing about why the container was crash-looping. Clearing before
+#   the underlying fault is fixed just restarts the loop that put it there.
+#
+# The Skip List Is Protection, Not Punishment
+#   A container lands here because restarting it repeatedly was making things worse, not
+#   better. The entry exists so the watchdog stops burning cycles and notifications on
+#   something only a human can fix.
+#
+# Persistent by Design
+#   The list lives on /boot/config and survives reboots deliberately. A crash loop that
+#   a reboot would clear is exactly the case where the watchdog would resume looping
+#   after the reboot — persistence is what stops that.
+#
+# Auto-Clear Is the Normal Path
+#   docker_watchdog.sh removes a container from the list on its own once it sees it
+#   running healthily. This tool is for the case where you have fixed the problem and
+#   do not want to wait for that, not the routine way entries leave the list.
+#
+# ==============================================================================================
+# CONFIGURATION
+# ==============================================================================================
+#
+# master.conf
+#
+#   DOCKER_WATCHDOG_FAILED_FILE
+#       Persistent skip list on /boot/config, shared with docker_watchdog.sh. Both must
+#       agree on the path or the watchdog will not see what this tool changes.
+#
+#   WATCHDOG_CONTAINER_RESTART_LIMIT / WATCHDOG_CONTAINER_RESTART_WINDOW
+#       The thresholds docker_watchdog.sh uses to decide a container belongs on the list.
+#       Shown here for context — this tool does not apply them, it only views and edits
+#       the resulting list.
+#
+# ==============================================================================================
 # OPERATIONAL SAFEGUARDS
 # ==============================================================================================
 #