Phase 3.5: Automation & Agents Plugin

Neues automation Plugin (app/plugins/builtins/automation/):
- 7 DB-Modelle: AgentDefinition, AgentVersion, AutomationDefinition,
  AutomationVersion, AutomationCronJob, AgentRun, AutomationRun
- Migration 0001_initial.sql mit allen Tabellen + RLS
- PluginManifest erweitert: agent_definitions, automation_templates,
  cron_jobs, heartbeat_configs, miniapps Contribution-Felder
- 21 API-Endpoints: /api/v1/automation (CRUD, execute, dry-run,
  runs, versions, restore, settings, miniapps) + /api/v1/agents
  (CRUD, execute, test-run, runs, versions, restore, tools, send-message)

Backend Features:
- Cron-Scheduler (scheduler.py): ARQ-basiert, liest CronJob-Tabelle,
  enqueued run_agent/run_automation, croniter fuer next_run_at
- Workflow-Timeout-Worker (workflow_timeout.py): prueft abgelaufene
  WorkflowInstances, setzt cancelled, sendet Notification
- Agent Runner (agent_runner.py): LiteLLM + ToolRegistry, proactive/
  reactive mode, Rate-Limiting, Budget-Limit, Infinite-Loop-Detection
- Automation Execution Engine (execution_engine.py): Condition
  evaluation (eq/ne/gt/lt/contains/exists), Actions (api_call/
  notification/workflow_start), Dry-Run mode
- Agent-to-Agent Communication (agent_comm.py): send_agent_message
  tool, kommunikation plugin integration
- Plugin-Beitraege: register/unregister on activate/deactivate,
  Konfliktloesung mit Plugin-Name als Prefix
- Heartbeat-Migration: ai_proactive heartbeat als Cron-Job
- Versionshistorie: Auto-Versioning bei Updates, Restore-Endpoint
- Settings: GET/PATCH /api/v1/automation/settings
- ARQ Worker: 11 functions, 2 cron_jobs (scheduler_tick 30s,
  check_workflow_timeouts 5min)

Frontend:
- AutomationDashboard.tsx: Automation Builder UI mit Trigger,
  Conditions, Actions, Execute, Dry-Run, Run-History, Versions
- AgentDashboard.tsx: Agent Builder UI mit Model, Tools, Prompt,
  Heartbeat, Rate-Limits, Execute, Test-Run, Agent-Chat
- AutomationSettings.tsx: Settings + MiniApp-Builder
- automation.ts: 24 React Query Hooks
- automation.ts types: TypeScript Interfaces
- routes/index.tsx: /automation, /agents, /settings/automation

Tests:
- 22 Frontend-Tests (AutomationDashboard, AgentDashboard, API) — alle bestanden
- Backend-Tests: test_automation.py (CRUD, versions, conditions, dry-run, rate-limiting)
- TSC: keine neuen Errors (nur pre-existing Dms.tsx)
- croniter dependency installiert

app/core/worker.py

@@ -6,6 +6,7 @@ import logging
 from typing import Any
 
 from arq.connections import RedisSettings
+from arq import cron
 
 from app.config import get_settings
 
@@ -48,6 +49,10 @@ from app.plugins.builtins.unified_search.jobs import (
     embedding_batch,
 )
 from app.plugins.builtins.ai_proactive.jobs import deep_analysis
+from app.plugins.builtins.automation.scheduler import scheduler_tick
+from app.plugins.builtins.automation.workflow_timeout import check_workflow_timeouts
+from app.plugins.builtins.automation.agent_runner import run_agent
+from app.plugins.builtins.automation.execution_engine import run_automation
 
 
 class WorkerSettings:
@@ -60,6 +65,10 @@ class WorkerSettings:
         reindex,
         embedding_batch,
         deep_analysis,
+        scheduler_tick,
+        check_workflow_timeouts,
+        run_agent,
+        run_automation,
     ]
     redis_settings = _get_redis_settings()
     on_startup = on_startup
@@ -67,3 +76,7 @@ class WorkerSettings:
     max_jobs = 10
     job_timeout = 300
     queue_name = "arq:queue"
+    cron_jobs = [
+        cron(scheduler_tick, second={0, 30}),
+        cron(check_workflow_timeouts, minute={0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55}),
+    ]