feat: implement multi-message mode and shuffle mode features

- Add multi-message mode with start/end/prompt markers
- Implement turn order shuffling with /turn-shuffling command
- Add channel mode state management
- Update hooks to handle multi-message mode behavior
- Update plugin config with new markers
- Update TASKLIST.md with completed tasks

plugin/turn-manager.ts

@@ -11,6 +11,8 @@
  *   - If sender IS in turn order → current = next after sender
  */
 
+import { isMultiMessageMode, exitMultiMessageMode } from "./core/channel-modes.js";
+
 export type ChannelTurnState = {
   /** Ordered accountIds for this channel (auto-populated, shuffled) */
   turnOrder: string[];
@@ -46,6 +48,26 @@ function shuffleArray<T>(arr: T[]): T[] {
   return a;
 }
 
+function reshuffleTurnOrder(channelId: string, currentOrder: string[], lastSpeaker?: string): string[] {
+  const shufflingEnabled = getChannelShuffling(channelId);
+  if (!shufflingEnabled) return currentOrder;
+  
+  const shuffled = shuffleArray(currentOrder);
+  
+  // If there's a last speaker and they're in the order, ensure they're not first
+  if (lastSpeaker && shuffled.length > 1 && shuffled[0] === lastSpeaker) {
+    // Find another speaker to swap with
+    for (let i = 1; i < shuffled.length; i++) {
+      if (shuffled[i] !== lastSpeaker) {
+        [shuffled[0], shuffled[i]] = [shuffled[i], shuffled[0]];
+        break;
+      }
+    }
+  }
+  
+  return shuffled;
+}
+
 // --- public API ---
 
 /**
@@ -176,6 +198,13 @@ export function onNewMessage(channelId: string, senderAccountId: string | undefi
   const state = channelTurns.get(channelId);
   if (!state || state.turnOrder.length === 0) return;
 
+  // Check for multi-message mode exit condition
+  if (isMultiMessageMode(channelId) && isHuman) {
+    // In multi-message mode, human messages don't trigger turn activation
+    // We only exit multi-message mode if the end marker is detected in a higher-level hook
+    return;
+  }
+
   if (isHuman) {
     // Human message: clear wait-for-human, restore original order if overridden, activate from first
     state.waitingForHuman = false;
@@ -330,6 +359,7 @@ export function onSpeakerDone(channelId: string, accountId: string, wasNoReply:
     state.noRepliedThisCycle = new Set();
   }
 
+  const prevSpeaker = state.currentSpeaker;
   const next = advanceTurn(channelId);
 
   // Check if override cycle completed (returned to first agent)
@@ -341,6 +371,18 @@ export function onSpeakerDone(channelId: string, accountId: string, wasNoReply:
     return null; // go dormant after override cycle completes
   }
 
+  // Check if we've completed a full cycle (all agents spoke once)
+  // This happens when we're back to the first agent in the turn order
+  const isFirstSpeakerAgain = next === state.turnOrder[0];
+  if (!wasNoReply && !state.overrideFirstAgent && next && isFirstSpeakerAgain && state.noRepliedThisCycle.size === 0) {
+    // Completed a full cycle without anyone NO_REPLYing - reshuffle if enabled
+    const newOrder = reshuffleTurnOrder(channelId, state.turnOrder, prevSpeaker);
+    if (newOrder !== state.turnOrder) {
+      state.turnOrder = newOrder;
+      console.log(`[dirigent][turn-debug] reshuffled turn order for channel=${channelId} newOrder=${JSON.stringify(newOrder)}`);
+    }
+  }
+
   return next;
 }