fix: exclude compaction notices from TTS transcript accumulation

Add isCompactionNotice flag to ReplyPayload and set it on both the
compaction start notice (agent-runner-execution.ts) and the completion
notice (agent-runner.ts). dispatch-from-config.ts skips accumulation
into accumulatedBlockText when the flag is set, so compaction status
lines (🧹 / ✅) are never synthesised into the fallback TTS audio for
block-streaming runs with tts.mode=final.

src/auto-reply/reply/agent-runner-execution.ts

@@ -428,6 +428,7 @@ export async function runAgentTurnWithFallback(params: {
                           text: "🧹 Compacting context...",
                           replyToId: currentMessageId,
                           replyToCurrent: true,
+                          isCompactionNotice: true,
                         });
                         await params.opts.onBlockReply(noticePayload);
                       }

src/auto-reply/reply/agent-runner.ts

@@ -433,6 +433,7 @@ export async function runReplyAgent(params: {
         text: completionText,
         replyToId: currentMessageId,
         replyToCurrent: true,
+        isCompactionNotice: true,
       });
       // Fire-and-forget with timeout — best-effort delivery; failure must not
       // propagate to the caller.

src/auto-reply/reply/dispatch-from-config.ts

@@ -582,8 +582,10 @@ export async function dispatchReplyFromConfig(params: {
             if (shouldSuppressReasoningPayload(payload)) {
               return;
             }
-            // Accumulate block text for TTS generation after streaming
-            if (payload.text) {
+            // Accumulate block text for TTS generation after streaming.
+            // Exclude compaction status notices — they are informational UI
+            // signals and must not be synthesised into the spoken reply.
+            if (payload.text && !payload.isCompactionNotice) {
               if (accumulatedBlockText.length > 0) {
                 accumulatedBlockText += "\n";
               }

src/auto-reply/types.ts

@@ -91,6 +91,10 @@ export type ReplyPayload = {
   /** Marks this payload as a reasoning/thinking block. Channels that do not
    *  have a dedicated reasoning lane (e.g. WhatsApp, web) should suppress it. */
   isReasoning?: boolean;
+  /** Marks this payload as a compaction status notice (start/end).
+   *  Should be excluded from TTS transcript accumulation so compaction
+   *  status lines are not synthesised into the spoken assistant reply. */
+  isCompactionNotice?: boolean;
   /** Channel-specific payload data (per-channel envelope). */
   channelData?: Record<string, unknown>;
 };