feat(agentscope): add memory system and automation job support

- Add consumer_registry and pipeline_registry for runtime orchestration
- Add Visibility schema for message filtering
- Add PipelineSpec for agent pipeline configuration
- Add automation job models and configuration
- Remove memory_prompt.py (consolidated into memory system)
- Update runtime components: context_loader, context_service, orchestrator, runner, tasks
- Update toolkit: tool_config, tool_middleware, custom tools (calendar, user_lookup)
- Add auth_helpers and calendar_domain utilities
- Add system_agents.yaml configuration

backend/src/schemas/automation/__init__.py

@@ -0,0 +1,20 @@
+from schemas.automation.config import (
+    AutomationAgentType,
+    AutomationContextSource,
+    AutomationContextWindowMode,
+    AutomationJobConfig,
+    AutomationMemoryContextConfig,
+    default_memory_job_config,
+)
+from schemas.automation.scheduler import DueAutomationJob, SchedulerDispatchCommand
+
+__all__ = [
+    "AutomationAgentType",
+    "AutomationContextSource",
+    "AutomationContextWindowMode",
+    "AutomationJobConfig",
+    "AutomationMemoryContextConfig",
+    "default_memory_job_config",
+    "DueAutomationJob",
+    "SchedulerDispatchCommand",
+]