fix: pipeline stop now halts all workers and flushes queues

Workers (ingestion, parser, extractor, aggregation, recommendation,
broker, lake-publisher) now check the pipeline:enabled Redis flag on
each loop iteration and sleep when disabled.

The toggle endpoint flushes all pipeline queues on disable so queued
jobs don't resume when workers eventually check. Broker/trading queues
are excluded from flush to avoid dropping in-flight orders.

services/ingestion/worker.py

@@ -41,6 +41,7 @@ from services.shared.redis_keys import (
     QUEUE_INGESTION,
     QUEUE_PARSING,
     dedupe_key,
+    is_pipeline_enabled,
     queue_key,
 )
 from services.shared.storage import (
@@ -265,6 +266,9 @@ async def main():
 
     try:
         while True:
+            if not await is_pipeline_enabled(rds):
+                await asyncio.sleep(2)
+                continue
             raw = await rds.lpop(queue)
             if raw:
                 job = json.loads(raw)