refactor(agent): capture subagent runtime before spawn

tests/agent/test_subagent.py

@@ -10,7 +10,13 @@ from nanobot.agent.subagent import SubagentManager, SubagentStatus
 from nanobot.agent.tools.filesystem import FileToolsConfig
 from nanobot.bus.queue import MessageBus
 from nanobot.config.schema import ToolsConfig
-from nanobot.providers.base import LLMProvider
+from nanobot.providers.base import GenerationSettings, LLMProvider
+from nanobot.utils.llm_runtime import LLMRuntime
+
+
+def _runtime(provider: LLMProvider) -> LLMRuntime:
+    provider.generation = GenerationSettings()
+    return LLMRuntime.capture(provider, "test", context_window_tokens=128_000)
 
 
 @pytest.mark.asyncio
@@ -19,10 +25,8 @@ async def test_subagent_uses_tool_loader():
     provider = MagicMock(spec=LLMProvider)
     provider.get_default_model.return_value = "test"
     sm = SubagentManager(
-        provider=provider,
         workspace=Path("/tmp"),
         bus=MessageBus(),
-        model="test",
         max_tool_result_chars=16_000,
     )
     tools = sm._build_tools()
@@ -39,10 +43,8 @@ async def test_subagent_build_tools_isolates_file_read_state(tmp_path):
     provider = MagicMock(spec=LLMProvider)
     provider.get_default_model.return_value = "test"
     sm = SubagentManager(
-        provider=provider,
         workspace=tmp_path,
         bus=MessageBus(),
-        model="test",
         max_tool_result_chars=16_000,
     )
 
@@ -60,10 +62,8 @@ def test_subagent_respects_file_tool_toggle(tmp_path):
     provider = MagicMock(spec=LLMProvider)
     provider.get_default_model.return_value = "test"
     sm = SubagentManager(
-        provider=provider,
         workspace=tmp_path,
         bus=MessageBus(),
-        model="test",
         max_tool_result_chars=16_000,
         tools_config=ToolsConfig(file=FileToolsConfig(enable=False)),
     )
@@ -87,10 +87,8 @@ async def test_subagent_forwards_fail_on_tool_error_to_runner(tmp_path):
     provider = MagicMock(spec=LLMProvider)
     provider.get_default_model.return_value = "test"
     sm = SubagentManager(
-        provider=provider,
         workspace=tmp_path,
         bus=MessageBus(),
-        model="test",
         max_tool_result_chars=16_000,
         fail_on_tool_error=False,
     )
@@ -106,7 +104,14 @@ async def test_subagent_forwards_fail_on_tool_error_to_runner(tmp_path):
         started_at=0.0,
     )
 
-    await sm._run_subagent("t1", "task", "label", {"channel": "cli", "chat_id": "direct"}, status)
+    await sm._run_subagent(
+        "t1",
+        "task",
+        "label",
+        {"channel": "cli", "chat_id": "direct"},
+        status,
+        _runtime(provider),
+    )
 
     spec = sm.runner.run.call_args.args[0]
     assert spec.fail_on_tool_error is False