feat(webui): add lightweight session messaging via mentions

tests/utils/test_webui_turn_helpers.py

@@ -1,22 +1,35 @@
 """Tests for WebSocket turn timing strip bookkeeping."""
 
+from typing import Any
 from unittest.mock import AsyncMock, MagicMock
 
 import pytest
 
 from nanobot.agent.tools.context import RequestContext, request_context
+from nanobot.agent.turn_delivery import TurnRoute
 from nanobot.bus.events import InboundMessage
-from nanobot.bus.outbound_events import GoalStatusEvent, TurnModelUpdatedEvent
-from nanobot.bus.runtime_events import RuntimeEventBus, RuntimeEventContext, TurnRuntimeAdmitted
+from nanobot.bus.outbound_events import (
+    GoalStatusEvent,
+    TurnModelUpdatedEvent,
+)
+from nanobot.bus.runtime_events import (
+    RuntimeEventBus,
+    RuntimeEventContext,
+    SessionTurnStarted,
+    TurnRuntimeAdmitted,
+)
 from nanobot.providers.base import GenerationSettings
 from nanobot.session import webui_turns as wth
 from nanobot.session.manager import SessionManager
+from nanobot.session.session_messages import SESSION_MESSAGE_METADATA_KEY
 from nanobot.utils.llm_runtime import LLMRuntime
 from nanobot.webui.metadata import WEBSOCKET_TURN_OWNER_METADATA_KEY
+from nanobot.webui.transcript import read_transcript_lines
 
 
 @pytest.fixture(autouse=True)
-def _clear_turn_wall_clock() -> None:
+def _clear_turn_wall_clock(tmp_path, monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setattr("nanobot.config.paths.get_data_dir", lambda: tmp_path)
     wth._WEBSOCKET_ACTIVE_TURNS.clear()
     wth._WEBSOCKET_TURN_WALL_STARTED_AT.clear()
     wth._WEBSOCKET_TURN_IDS.clear()
@@ -223,3 +236,90 @@ async def test_fallback_model_ignores_non_websocket_requests() -> None:
         await observer("fallback")
 
     bus.publish_outbound.assert_not_awaited()
+
+
+@pytest.mark.asyncio
+async def test_session_route_does_not_duplicate_already_projected_input(
+    tmp_path,
+    monkeypatch,
+) -> None:
+    monkeypatch.setattr("nanobot.config.paths.get_data_dir", lambda: tmp_path)
+    sessions = SessionManager(tmp_path / "sessions")
+    target = sessions.get_or_create("websocket:target")
+    target.metadata["webui"] = True
+    sessions.save(target)
+    metadata = {
+        SESSION_MESSAGE_METADATA_KEY: {
+            "message_id": "message-1",
+            "created_at_ms": 1234,
+            "expect_reply": True,
+            "source": {
+                "name": "reviewer",
+                "session_key": "websocket:source",
+                "handle_id": "handle_11111111111111111111111111111111",
+                "color_slot": 3,
+            },
+            "target": {
+                "name": "implementer",
+                "session_key": "websocket:target",
+            },
+        }
+    }
+    msg = InboundMessage(
+        channel="system",
+        sender_id="session",
+        chat_id="websocket:target",
+        content="Please review this.",
+        metadata=metadata,
+        session_key_override="websocket:target",
+        require_existing_session=True,
+    )
+
+    routed = wth.WebuiTurnRoutePolicy(sessions)(
+        msg,
+        "websocket:target",
+        TurnRoute(channel="websocket", chat_id="target"),
+    )
+
+    assert routed.publish_lifecycle is True
+    assert read_transcript_lines("websocket:target") == []
+
+    bus = MagicMock()
+    bus.publish_outbound = AsyncMock()
+    coordinator = wth.WebuiTurnCoordinator(
+        bus=bus,
+        sessions=sessions,
+        schedule_background=lambda _task: None,
+    )
+    await coordinator._handle_session_turn_started(SessionTurnStarted(
+        context=RuntimeEventContext(
+            channel=routed.channel,
+            chat_id=routed.chat_id,
+            session_key="websocket:target",
+            metadata=routed.metadata,
+        ),
+        content=msg.content,
+    ))
+
+    assert read_transcript_lines("websocket:target") == []
+    bus.publish_outbound.assert_not_awaited()
+
+
+def _session_message_metadata() -> dict[str, Any]:
+    return {
+        SESSION_MESSAGE_METADATA_KEY: {
+            "message_id": "message-1",
+            "created_at_ms": 1,
+            "expect_reply": True,
+            "source": {
+                "name": "reviewer",
+                "session_key": "websocket:source",
+                "handle_id": "handle_11111111111111111111111111111111",
+                "color_slot": 1,
+            },
+            "target": {
+                "name": "implementer",
+                "session_key": "websocket:target",
+            },
+        }
+    }