fix(slack): preserve thread context for proactive replies

Capture Slack thread metadata for cron and message-tool deliveries so replies stay in the originating thread, and hydrate first thread mentions with recent Slack context.

Made-with: Cursor

tests/agent/test_loop_tool_context.py

@@ -0,0 +1,90 @@
+from pathlib import Path
+from unittest.mock import MagicMock
+
+import pytest
+
+from nanobot.agent.loop import AgentLoop
+from nanobot.bus.queue import MessageBus
+from nanobot.providers.base import LLMResponse, ToolCallRequest
+
+
+class _ContextRecordingTool:
+    name = "cron"
+    concurrency_safe = False
+
+    def __init__(self) -> None:
+        self.contexts: list[dict] = []
+
+    def set_context(
+        self,
+        channel: str,
+        chat_id: str,
+        metadata: dict | None = None,
+        session_key: str | None = None,
+    ) -> None:
+        self.contexts.append({
+            "channel": channel,
+            "chat_id": chat_id,
+            "metadata": metadata,
+            "session_key": session_key,
+        })
+
+    async def execute(self, **_kwargs) -> str:
+        return "created"
+
+
+class _Tools:
+    def __init__(self, tool: _ContextRecordingTool) -> None:
+        self.tool = tool
+
+    def get(self, name: str):
+        return self.tool if name == "cron" else None
+
+    def get_definitions(self) -> list:
+        return []
+
+    def prepare_call(self, name: str, arguments: dict):
+        return (self.tool, arguments, None) if name == "cron" else (None, arguments, None)
+
+
+@pytest.mark.asyncio
+async def test_loop_hook_preserves_metadata_when_resetting_tool_context(tmp_path: Path) -> None:
+    provider = MagicMock()
+    calls = {"n": 0}
+
+    async def chat_with_retry(**_kwargs):
+        calls["n"] += 1
+        if calls["n"] == 1:
+            return LLMResponse(
+                content=None,
+                tool_calls=[ToolCallRequest(id="call_1", name="cron", arguments={"action": "add"})],
+            )
+        return LLMResponse(content="done", tool_calls=[])
+
+    provider.chat_with_retry = chat_with_retry
+    provider.get_default_model.return_value = "test-model"
+
+    loop = AgentLoop(
+        bus=MessageBus(),
+        provider=provider,
+        workspace=tmp_path,
+        model="test-model",
+    )
+    cron = _ContextRecordingTool()
+    loop.tools = _Tools(cron)
+
+    metadata = {"slack": {"thread_ts": "111.222", "channel_type": "channel"}}
+    await loop._run_agent_loop(
+        [],
+        channel="slack",
+        chat_id="C123",
+        metadata=metadata,
+        session_key="slack:C123:111.222",
+    )
+
+    assert cron.contexts[-1] == {
+        "channel": "slack",
+        "chat_id": "C123",
+        "metadata": metadata,
+        "session_key": "slack:C123:111.222",
+    }