rename: fix remaining failover refs in fallback.sh, fallback_test.sh, array_started.sh, user_script_plug-in.sh

user_script_plug-in.sh

@@ -53,7 +53,7 @@
 #   v1.0 — Initial template
 #   v1.1 — MAX_RSYNC_PROCS removed, --status flag, full directory tree, changelog
 #   v1.2 — Docker Essentials, Media, Transcodes, System Watchdog added
-#   v1.3 — Failover script added
+#   v1.3 — Fallback script added
 #   v1.4 — WebGUI watchdog, ZFS snapshot, Docker network connect, schedules section
 #   v1.5 — media_management.sh orchestrator, corrected filenames, git repo section
 #   v1.6 — lidarr_cleanup.sh, sonarr_cleanup.sh, radarr_cleanup.sh added
@@ -69,7 +69,7 @@
 #   v2.2 — Orchestrators at top with full inline detail. All child scripts listed
 #           individually below for standalone use. Inline descriptions on every entry.
 #           Correct schedules verified against script headers. sunday_morning_coffee_report
-#           and rsync_emby_failover added as separate scheduled entries.
+#           and rsync_emby_fallback added as separate scheduled entries.
 #   v2.3 — intermediate_sync_maintenance.sh new 4-hour orchestrator (arr_sync + artwork).
 #           docker_update.sh + docker_update_remaining.sh: daily/weekly image pulls.
 #           downloaders_reset.sh: slskd + SABnzbd + qBittorrent maintenance.
@@ -402,7 +402,7 @@
 # DIGEST_PROFILE options (master.conf):
 #   always    notify every run regardless — daily digest even when healthy
 #   smart     notify only when something worth reporting is found:
-#               active watchdog strikes, non-NORMAL failover, cert within CERT_WARN_DAYS,
+#               active watchdog strikes, non-NORMAL fallback state, cert within CERT_WARN_DAYS,
 #               bandwidth event exceeded BANDWIDTH_WARN_GB
 #   weekly    notify once per week on DIGEST_DAY (Sunday), silent all other days
 #
@@ -475,7 +475,7 @@
 #   Tier 2 at 4hr:   NextCloud + Immich + Jellyseerr
 #   Tier 3 at 12hr:  AdGuard + Gitea + uptime monitoring
 #   Tier 4 at 24hr:  arrs + downloaders
-# Auth stack (NPM, Authelia, LLDAP) runs warm on both servers always — no failover startup delay.
+# Auth stack (NPM, Authelia, LLDAP) runs warm on both servers always — no fallback startup delay.
 # DDNS: one domain, one DDNS container active at all times. Split-brain prevented by design.
 # Handback: stop remote DDNS → rsync writeback → start containers → start local DDNS.
 #