feat(agents): autonomous guard-railed DML on source DBs for Debezium CDC

Add api/agent_ops.py: background loop performs small INSERT/UPDATE/DELETE on
public.sales_orders (PG), hr.employee_events (MySQL) and supplychain.events
(Mongo). Agent rows are tagged (notes/atc_agent); UPDATE/DELETE only ever touch
agent-created rows. Env kill-switch + interval + per-tick row cap. Endpoints
/api/agent-ops/{status,toggle,run-once}. Loop started in lifespan.

api/main.py

@@ -42,6 +42,7 @@ from pipeline_ops import router as pipeline_router
 from hadoop_analytics import router as hadoop_router
 from elasticsearch_api import router as elasticsearch_router
 from sql_console import router as sql_router
+from agent_ops import router as agent_ops_router, agent_dml_loop
 from ssh_terminal import ssh_session
 from node_registry import NODE_IDS, NODE_AGENT, NODE_REGISTRY, is_node_id
 from node_ops import build_node_detail, probe_node, run_node_probe_task
@@ -711,9 +712,11 @@ async def lifespan(app: FastAPI):
         meta = NODE_REGISTRY[nid]
         await terminal_log(nid, f"{meta['label']} shell ready — click node to connect", level="info", phase="boot")
     task = asyncio.create_task(heartbeat_loop())
+    dml_task = asyncio.create_task(agent_dml_loop())
     add_feed("infra-sentinel", "ATC Command Center API online", "info")
     yield
     task.cancel()
+    dml_task.cancel()
     if redis_client:
         await redis_client.close()
 
@@ -725,6 +728,7 @@ app.include_router(pipeline_router)
 app.include_router(hadoop_router)
 app.include_router(elasticsearch_router)
 app.include_router(sql_router)
+app.include_router(agent_ops_router)
 app.add_middleware(
     CORSMiddleware,
     allow_origins=["*"],