fix(message): limit session recording to proactive sends

Only mark message-tool deliveries for channel-session recording while cron jobs are running, avoiding duplicate session writes during normal user turns.

Made-with: Cursor

tests/tools/test_message_tool.py

@@ -1,6 +1,7 @@
 import pytest
 
 from nanobot.agent.tools.message import MessageTool
+from nanobot.bus.events import OutboundMessage
 
 
 @pytest.mark.asyncio
@@ -29,3 +30,23 @@ async def test_message_tool_rejects_malformed_buttons(bad) -> None:
         content="hi", channel="telegram", chat_id="1", buttons=bad,
     )
     assert result == "Error: buttons must be a list of list of strings"
+
+
+@pytest.mark.asyncio
+async def test_message_tool_marks_channel_delivery_only_when_enabled() -> None:
+    sent: list[OutboundMessage] = []
+
+    async def _send(msg: OutboundMessage) -> None:
+        sent.append(msg)
+
+    tool = MessageTool(send_callback=_send)
+
+    await tool.execute(content="normal", channel="telegram", chat_id="1")
+    token = tool.set_record_channel_delivery(True)
+    try:
+        await tool.execute(content="cron", channel="telegram", chat_id="1")
+    finally:
+        tool.reset_record_channel_delivery(token)
+
+    assert sent[0].metadata == {}
+    assert sent[1].metadata == {"_record_channel_delivery": True}