RESUME: check the AFC lane, add AFC_CLEAR_ALL_MESSAGES

PAUSE stores the lane the print needs (AFC's next_lane during a failed
tool change, otherwise the loaded lane). RESUME stops with an error when
another lane or none is loaded; RESUME LANE_CHECK=0 skips the check.

AFC_CLEAR_ALL_MESSAGES clears AFC's whole message queue
(AFC_CLEAR_MESSAGE only removes the first message).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

macros/afc/lane_tools.cfg

@@ -1,4 +1,4 @@
-# AFC lane tools: LANE_FEED_UNTIL_HUB_OPEN, LANE_FEED_ABORT
+# AFC lane tools: LANE_FEED_UNTIL_HUB_OPEN, LANE_FEED_ABORT, AFC_CLEAR_ALL_MESSAGES
 
 #####################################################################
 ## unloading help
@@ -98,3 +98,16 @@ gcode:
 #     T1 ; Unload
 #     G4 P3000 ; Wait 3s
 #   {% endfor %}
+
+#####################################################################
+## AFC messages
+#####################################################################
+# AFC queues every error and warning; the UI shows only the first one and
+# AFC_CLEAR_MESSAGE removes only that one. AFC does not expose the queue
+# length, so clear MAX times (clearing an empty queue does nothing).
+[gcode_macro AFC_CLEAR_ALL_MESSAGES]
+description: Clear all AFC error and warning messages (MAX=50)
+gcode:
+    {% for i in range(params.MAX|default(50)|int) %}
+    AFC_CLEAR_MESSAGE
+    {% endfor %}