feat(agent-runner): integrate AgentRunner Protocol v1 with plugin system

Phase 0 integration complete - verified minimal loop with local-agent stub runner.

Changes:
- Add AgentRunOrchestrator for plugin-based agent execution
- Add AgentResultNormalizer for Protocol v1 result conversion
- Add AgentRunnerDescriptor for runner ID parsing (plugin:author/name/runner)
- Update chat handler to use new orchestrator instead of direct runner lookup
- Add plugin handler methods for list_agent_runners and run_agent
- Add connector methods for AgentRunner protocol forwarding
- Update pipeline API to include runner options in metadata
- Add integration docs and implementation plan

Integration verified:
- Runner: plugin:langbot/local-agent/default
- Input: "你好"
- Output: [stub] Echo: 你好
- Date: 2026-05-10 10:09

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/langbot/pkg/core/app.py

@@ -4,6 +4,7 @@ import logging
 import asyncio
 import traceback
 import os
+from typing import TYPE_CHECKING
 
 from ..platform import botmgr as im_mgr
 from ..platform.webhook_pusher import WebhookPusher
@@ -46,6 +47,9 @@ from ..telemetry import telemetry as telemetry_module
 from ..survey import manager as survey_module
 from ..skill import manager as skill_mgr
 
+if TYPE_CHECKING:
+    from ..agent.runner import AgentRunnerRegistry, AgentRunOrchestrator
+
 
 class Application:
     """Runtime application object and context"""
@@ -165,6 +169,11 @@ class Application:
 
     maintenance_service: maintenance_service.MaintenanceService = None
 
+    # Agent runner subsystem
+    agent_runner_registry: AgentRunnerRegistry = None
+
+    agent_run_orchestrator: AgentRunOrchestrator = None
+
     def __init__(self):
         pass
 

src/langbot/pkg/core/stages/build_app.py

@@ -39,6 +39,7 @@ from ...vector import mgr as vectordb_mgr
 from .. import taskmgr
 from ...telemetry import telemetry as telemetry_module
 from ...survey import manager as survey_module
+from ...agent.runner import AgentRunnerRegistry, AgentRunOrchestrator
 
 
 @stage.stage_class('BuildAppStage')
@@ -194,5 +195,12 @@ class BuildAppStage(stage.BootingStage):
         await plugin_connector_inst.initialize()
         ap.plugin_connector = plugin_connector_inst
 
+        # Initialize agent runner subsystem
+        agent_runner_registry_inst = AgentRunnerRegistry(ap)
+        ap.agent_runner_registry = agent_runner_registry_inst
+
+        agent_run_orchestrator_inst = AgentRunOrchestrator(ap, agent_runner_registry_inst)
+        ap.agent_run_orchestrator = agent_run_orchestrator_inst
+
         ctrl = controller.Controller(ap)
         ap.ctrl = ctrl