feat(core): publish tool.result on the bus for the activity panel

tests/test_conversations.py

@@ -12,6 +12,9 @@ from claude_agent_sdk import (
     ResultMessage,
     StreamEvent,
     TextBlock,
+    ToolResultBlock,
+    ToolUseBlock,
+    UserMessage,
     project_key_for_directory,
 )
 
@@ -655,3 +658,40 @@ def test_agent_kinds_follow_prompts(tmp_path: Path) -> None:
             kinds=("master", "deep"),
             prompts=Prompts(master=()),
         )
+
+
+async def test_observer_publishes_tool_results_for_the_panel(world: World) -> None:
+    seen: list[dict[str, Any]] = []
+
+    async def collect() -> None:
+        async for event in world.bus.stream(conversation_id="c1"):
+            seen.append(event)
+
+    task = asyncio.create_task(collect())
+    await asyncio.sleep(0)
+    observe = world.conversations._observer("c1", "t1", "user")
+    observe(
+        AssistantMessage(
+            content=[ToolUseBlock(id="toolu_1", name="Bash", input={"command": "ls"})],
+            model="m",
+            parent_tool_use_id="toolu_0",
+        )
+    )
+    observe(
+        UserMessage(
+            content=[
+                ToolResultBlock(tool_use_id="toolu_1", content="a\nb", is_error=False)
+            ],
+            parent_tool_use_id="toolu_0",
+        )
+    )
+    observe(UserMessage(content="plain text, no tool result"))
+    await asyncio.sleep(0.05)
+    task.cancel()
+    assert [e["type"] for e in seen] == ["tool", "tool.result"]
+    tool, result = seen
+    assert tool["tool_use_id"] == "toolu_1" and tool["parent_tool_use_id"] == "toolu_0"
+    assert result["tool_use_id"] == "toolu_1"
+    assert result["parent_tool_use_id"] == "toolu_0"
+    assert result["turn_id"] == "t1" and result["is_error"] is False
+    assert result["content"] == "a\nb"