Consolidate persistence style opcodes into toggles

Replace the 6 separate opcodes (0x00-0x02 for InProgress, 0x04-0x06
for Completed) with 3 toggle opcodes (0x00-0x02) that flip the
persistence style for each node. When toggling back to Completed, the
existing guard that prevents switching while monitors are pending is
preserved.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: joostjager

fuzz/src/chanmon_consistency.rs

@@ -2082,52 +2082,25 @@ pub fn do_test<Out: Output + MaybeSend + MaybeSync>(
 			// In general, we keep related message groups close together in binary form, allowing
 			// bit-twiddling mutations to have similar effects. This is probably overkill, but no
 			// harm in doing so.
-			0x00 => {
-				*monitor_a.persister.update_ret.lock().unwrap() =
-					ChannelMonitorUpdateStatus::InProgress;
-			},
-			0x01 => {
-				*monitor_b.persister.update_ret.lock().unwrap() =
-					ChannelMonitorUpdateStatus::InProgress;
-			},
-			0x02 => {
-				*monitor_c.persister.update_ret.lock().unwrap() =
-					ChannelMonitorUpdateStatus::InProgress;
-			},
-			0x04 => {
-				let has_pending = monitor_a
-					.latest_monitors
-					.lock()
-					.unwrap()
-					.values()
-					.any(|s| !s.pending_monitors.is_empty());
-				if !has_pending {
-					*monitor_a.persister.update_ret.lock().unwrap() =
-						ChannelMonitorUpdateStatus::Completed;
-				}
-			},
-			0x05 => {
-				let has_pending = monitor_b
-					.latest_monitors
-					.lock()
-					.unwrap()
-					.values()
-					.any(|s| !s.pending_monitors.is_empty());
-				if !has_pending {
-					*monitor_b.persister.update_ret.lock().unwrap() =
-						ChannelMonitorUpdateStatus::Completed;
-				}
-			},
-			0x06 => {
-				let has_pending = monitor_c
-					.latest_monitors
-					.lock()
-					.unwrap()
-					.values()
-					.any(|s| !s.pending_monitors.is_empty());
-				if !has_pending {
-					*monitor_c.persister.update_ret.lock().unwrap() =
-						ChannelMonitorUpdateStatus::Completed;
+			0x00 | 0x01 | 0x02 => {
+				let monitor = match v {
+					0x00 => &monitor_a,
+					0x01 => &monitor_b,
+					_ => &monitor_c,
+				};
+				let mut ret = monitor.persister.update_ret.lock().unwrap();
+				if *ret == ChannelMonitorUpdateStatus::Completed {
+					*ret = ChannelMonitorUpdateStatus::InProgress;
+				} else {
+					let has_pending = monitor
+						.latest_monitors
+						.lock()
+						.unwrap()
+						.values()
+						.any(|s| !s.pending_monitors.is_empty());
+					if !has_pending {
+						*ret = ChannelMonitorUpdateStatus::Completed;
+					}
 				}
 			},