fix(armbian-leds): don't persist brightness for any active trigger

armbian-led-state-save.sh wrote brightness for every LED with a
writable brightness file. For LEDs whose trigger is active (e.g.
disk-activity, heartbeat, phy0tpt, eth0:link, mmc0, cpu, timer,
pattern, usb-*, nand-disk) brightness is the trigger's
instantaneous output (a momentary blink-state captured at
shutdown), not configuration. Persisting it produced ghost-LED
bugs on restore (cable-up while unplugged, rtw88 wifi flapping
0/1) and constant noise in /etc/armbian-leds.conf on every
shutdown — visible to anyone with etckeeper / etc-diff alerts.

Fix: strip brightness whenever trigger != none. The previous
workaround stripped only \`*:link\` triggers (commit 2960ffa)
and is now subsumed. trigger=none preserves brightness as before
(it is genuine config there).

Token-safe filter (whole-word match, not substring): the original
substitution \${PARAMS//brightness/} would corrupt sibling files
like \`max_brightness\` -> \`max_\`, breaking the read loop under
set -e. Bash-only loop because store_led() reassigns PATH to the
sysfs led path, so external commands wouldn't be found here.

Forum thread: https://forum.armbian.com/topic/57284-

Restore-script's brightness=0 skip guard becomes redundant for
active triggers but harmless.

Assisted-by: Claude:claude-opus-4.7

Author: iav

packages/bsp/common/usr/lib/armbian/armbian-led-state-save.sh

@@ -40,10 +40,29 @@ function store_led() {
 	COMMAND_PARAMS="$CMD_FIND $PATH/ -maxdepth 1 -type f ! -iname uevent ! -iname trigger -perm /u+w -printf %f\\n"
 	PARAMS=$($COMMAND_PARAMS)
 
-	# In case trigger is representing link-state for any network, use
-	# bash substitution to remove the brightness parameter and avoid
-	# ghost wan/lan/etc (led up while cable unplugged)
-	[[ "$TRIGGER_VALUE" == *":link" ]] && PARAMS=${PARAMS//"brightness"/}
+	# brightness has two distinct meanings depending on the trigger:
+	#   trigger=none  → brightness is config (static value, persist it).
+	#   trigger=*     → brightness is the trigger's instantaneous output
+	#                   (blink-state at shutdown), persisting it is noise
+	#                   and causes ghost-LED bugs on restore (e.g. ":link"
+	#                   triggers showed cable-up while unplugged; rtw88
+	#                   wifi flapped 0/1 in /etc/armbian-leds.conf on every
+	#                   shutdown). Strip for any non-none trigger.
+	# Subsumes the earlier ":link"-only workaround (commit 2960ffaff).
+	# Forum thread: https://forum.armbian.com/topic/57284-
+	# Token-safe filter (whole-word match): the previous ${PARAMS//brightness/}
+	# substring substitution would also corrupt sibling files like
+	# `max_brightness` -> `max_`, breaking the read loop below under set -e.
+	# Bash-only (no `awk` etc.) because store_led() reassigns PATH to the
+	# sysfs led path, so external commands wouldn't be found here.
+	if [[ "$TRIGGER_VALUE" != "none" ]]; then
+		declare _filtered=""
+		for _p in $PARAMS; do
+			[[ "$_p" == "brightness" ]] && continue
+			_filtered+="$_p"$'\n'
+		done
+		PARAMS="$_filtered"
+	fi
 
 	for PARAM in $PARAMS; do