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.

Arrs_Stack/lidarr_duplicate_artist_cleanup.sh

@@ -52,6 +52,56 @@
 #   output. Only ambiguous (overlapping-album) pairs produce a notification.
 #
 # ==============================================================================================
+# OPERATIONAL SAFEGUARDS
+# ==============================================================================================
+#
+# Root Enforcement
+#   Required by the container interaction and state writes.
+#
+# Lock Acquisition
+#   acquire_lock prevents overlapping runs racing on the same artist IDs.
+#
+# Host Detection
+#   detect_hosts() aliases LIDARR_URL / LIDARR_API_KEY.
+#
+# jq Dependency Check
+#   Fails fast if jq is missing — duplicate detection and every file-count read
+#   depend on it, and an absent jq would evaluate counts to empty and make every
+#   artist look like a zero-file phantom.
+#
+# API Reachability + Version Gate
+#   check_api then check_arr_version against LIDARR_VERSION_MAJOR before any read.
+#
+# Empty Library Abort
+#   A response of 0 artists aborts. An empty list is indistinguishable from
+#   "no duplicates" and must never be read as a clean result.
+#
+# Tracked-Count Floor
+#   check_tracked_count_floor against the baseline shared with lidarr_cleanup.sh.
+#   A library-wide desync — mid full-rescan, for example — makes trackFileCount read
+#   far below reality for many artists at once. Confirmed 2026-07-16: without this,
+#   both sides of a genuinely-real duplicate (ROMES) read as 0-file phantoms and the
+#   wrong one would have been deleted. Deliberately reuses lidarr_cleanup.sh's own
+#   baseline so every script depending on tracked counts shares one answer to "is
+#   Lidarr's data trustworthy right now" rather than forming a separate opinion.
+#
+# Files Never Deleted
+#   Removal passes deleteFiles=false. Only the phantom Lidarr entry is dropped;
+#   nothing on disk is touched, so a wrong call costs a re-add, not media.
+#
+# Phantom-Only Deletion
+#   Only the zero-file side of a duplicate pair is ever removed. If both sides hold
+#   files, or neither does unambiguously, the pair is flagged for manual review
+#   instead — the script never picks a winner between two real artists.
+#
+# Manual Review Reporting
+#   Flagged pairs are named in the summary and notification so an ambiguous
+#   duplicate surfaces as a decision to make rather than disappearing silently.
+#
+# Dry Run Support
+#   --dry-run reports every deletion and exclusion and performs none.
+#
+# ==============================================================================================
 # CONFIGURATION
 # ==============================================================================================
 #