Run scheduled tasks through application database

docs/DEPLOYMENT.md

@@ -109,8 +109,11 @@ The workflow:
 
 The short outage is limited to backup, migration, and container startup. This
 follows the database-preservation policy while minimizing data-entry downtime.
-The scheduler runs automated system messages, Oversight consolidation, and
-email digest checks once per minute.
+The scheduler calls a bearer-authenticated endpoint on the application service
+once per minute. Scheduled message delivery therefore uses the web process's
+existing embedded-database connection instead of opening the locked database
+from a second process. The endpoint runs automated system messages, Oversight
+consolidation, and email digest checks and is not published through a host port.
 
 ## Initial development-data bootstrap