Fix dead/incorrect vars and consolidate duplicated logic into common.sh

Codebase-wide audit pass: fixed real bugs (SSH hangs missing BatchMode,
local-outside-function no-ops, variable name collisions, a truncated
ratio calc, wrong state-dir path, DARK vs NO_INTERNET drift, and more),
then pulled logic that was duplicated across multiple scripts — arr
cleanup safety gates, docker restart ordering, container maintenance
stop/restart, watchdog state-file helpers, partnership role resolution,
cert expiry checks, remote node discovery, and TMDB discovery scoring —
into common.sh so each now has a single implementation.

Rsync/rsync.sh

@@ -56,7 +56,7 @@
 #
 # Remote Health Pre-flights
 #   check_connectivity() — Tailscale IP reachable before any SSH
-#   check_remote_rootfs() — aborts if remote rootfs exceeds ROOTFS_WARN_PCT
+#   check_remote_rootfs() — aborts if remote rootfs exceeds ROOTFS_WARN
 #   check_remote_share() — aborts if target directory missing or empty on remote
 #   check_remote_disks() — verifies all backing disks online on remote
 #
@@ -98,7 +98,7 @@
 #   SLEEP
 #       Default seconds between retry attempts. (default: 60)
 #
-#   ROOTFS_WARN_PCT
+#   ROOTFS_WARN
 #       Abort threshold for remote rootfs percentage full. (default: 75)
 #
 #   PROFILES["profile_KEY"]
@@ -223,6 +223,11 @@ VV_LAST_LOG="/tmp/unraid_locks/rsync_${PROFILE_NAME}.last.log"
 exec 1> >(tee -a "$VV_LIVE_LOG") 2>&1
 
 # ── Load profile settings ─────────────────────────────────────────────────────────────────────
+# NOTE: DEFAULT_RSYNC_OPTS and PROFILE_RSYNC_OPTS are bash arrays defined in master.conf —
+# any "$BW_LIMIT" inside them is expanded once, when master.conf is sourced, before this
+# override runs. So this recomputed $BW_LIMIT only affects the log line below and --status;
+# it does NOT change the actual rsync --bwlimit unless a profile also bakes its own
+# --bwlimit="${PROFILE_BW_LIMIT[name]}" directly into that profile's PROFILE_RSYNC_OPTS entry.
 BW_LIMIT=${PROFILE_BW_LIMIT[$PROFILE_NAME]:-$BW_LIMIT}
 RETRY_COUNT=${PROFILE_RETRY_COUNT[$PROFILE_NAME]:-$RETRY_COUNT}
 SLEEP=${PROFILE_SLEEP[$PROFILE_NAME]:-$SLEEP}