(docs) Reframe documentation around Django-first operations

Update the README to describe pobsync as a Django-first, SQL-backed
service with the control panel as the primary operational interface.

Move CLI examples out of the normal workflow and document them as
maintainer tooling for debugging, services, and migration tasks.

README.md

@@ -3,9 +3,10 @@
 `pobsync` is a pull-based backup service. It runs on a central backup server and pulls data from remote machines via
 rsync over SSH.
 
-The current refactor is SQL-first:
+The current refactor is Django-first and SQL-backed:
 
-- Django is the management layer and source of truth.
+- The Django control panel is the primary interface for setup and operations.
+- The database is the source of truth for hosts, schedules, runs, snapshots, credentials, and retention settings.
 - SQLite is the default database; MariaDB is optional.
 - Backups use the existing rsync snapshot engine internally.
 - Scheduling is handled by a Django scheduler service, not host cron.
@@ -159,6 +160,6 @@ systemctl status pobsync-web pobsync-worker pobsync-scheduler
 
 ## Development
 
-Development, Docker, migration helper commands, and architecture notes live in:
+Development, Docker, maintainer tooling, and architecture notes live in:
 
 - [docs/development.md](docs/development.md)