fix: keep rapid telegram follow-ups from getting cut off

tests/gateway/test_session_race_guard.py

@@ -14,7 +14,7 @@ from unittest.mock import AsyncMock, MagicMock, patch
 import pytest
 
 from gateway.config import GatewayConfig, Platform, PlatformConfig
-from gateway.platforms.base import MessageEvent, MessageType
+from gateway.platforms.base import MessageEvent, MessageType, merge_pending_message_event
 from gateway.run import GatewayRunner, _AGENT_PENDING_SENTINEL
 from gateway.session import SessionSource, build_session_key
 
@@ -184,6 +184,80 @@ async def test_second_message_during_sentinel_queued_not_duplicate():
         await task1
 
 
+def test_merge_pending_message_event_merges_text_and_photo_followups():
+    pending = {}
+    source = SessionSource(
+        platform=Platform.TELEGRAM,
+        chat_id="12345",
+        chat_type="dm",
+        user_id="u1",
+    )
+    session_key = build_session_key(source)
+
+    text_event = MessageEvent(
+        text="first follow-up",
+        message_type=MessageType.TEXT,
+        source=source,
+    )
+    photo_event = MessageEvent(
+        text="see screenshot",
+        message_type=MessageType.PHOTO,
+        source=source,
+        media_urls=["/tmp/test.png"],
+        media_types=["image/png"],
+    )
+
+    merge_pending_message_event(pending, session_key, text_event, merge_text=True)
+    merge_pending_message_event(pending, session_key, photo_event, merge_text=True)
+
+    merged = pending[session_key]
+    assert merged.message_type == MessageType.PHOTO
+    assert merged.text == "first follow-up\n\nsee screenshot"
+    assert merged.media_urls == ["/tmp/test.png"]
+    assert merged.media_types == ["image/png"]
+
+
+@pytest.mark.asyncio
+async def test_recent_telegram_text_followup_is_queued_without_interrupt():
+    runner = _make_runner()
+    event = _make_event(text="follow-up")
+    session_key = build_session_key(event.source)
+
+    fake_agent = MagicMock()
+    fake_agent.get_activity_summary.return_value = {"seconds_since_activity": 0}
+    runner._running_agents[session_key] = fake_agent
+    import time as _time
+    runner._running_agents_ts[session_key] = _time.time()
+
+    result = await runner._handle_message(event)
+
+    assert result is None
+    fake_agent.interrupt.assert_not_called()
+    adapter = runner.adapters[Platform.TELEGRAM]
+    assert adapter._pending_messages[session_key].text == "follow-up"
+
+
+@pytest.mark.asyncio
+async def test_recent_telegram_followups_append_in_pending_queue():
+    runner = _make_runner()
+    first = _make_event(text="part one")
+    second = _make_event(text="part two")
+    session_key = build_session_key(first.source)
+
+    fake_agent = MagicMock()
+    fake_agent.get_activity_summary.return_value = {"seconds_since_activity": 0}
+    runner._running_agents[session_key] = fake_agent
+    import time as _time
+    runner._running_agents_ts[session_key] = _time.time()
+
+    await runner._handle_message(first)
+    await runner._handle_message(second)
+
+    fake_agent.interrupt.assert_not_called()
+    adapter = runner.adapters[Platform.TELEGRAM]
+    assert adapter._pending_messages[session_key].text == "part one\npart two"
+
+
 # ------------------------------------------------------------------
 # Test 5: Sentinel not placed for command messages
 # ------------------------------------------------------------------
@@ -273,6 +347,7 @@ async def test_stop_hard_kills_running_agent():
 
     # Simulate a running (possibly hung) agent
     fake_agent = MagicMock()
+    fake_agent.get_activity_summary.return_value = {"seconds_since_activity": 0}
     runner._running_agents[session_key] = fake_agent
 
     # Send /stop
@@ -305,6 +380,7 @@ async def test_stop_clears_pending_messages():
     )
 
     fake_agent = MagicMock()
+    fake_agent.get_activity_summary.return_value = {"seconds_since_activity": 0}
     runner._running_agents[session_key] = fake_agent
     runner._pending_messages[session_key] = "some queued text"