## Summary

- Add per-host rsync bandwidth limit overrides with inherit/unlimited semantics.
- Store the effective bwlimit in run metadata/results and show it in host/run detail views.
- Document recommended starting values for VPN and remote backups.

## Tests
- `.venv/bin/python manage.py makemigrations --check --dry-run`
- `.venv/bin/python manage.py test src.pobsync_backend.tests.test_django_config_source.DjangoConfigSourceTests.test_returns_effective_config_from_database src.pobsync_backend.tests.test_django_config_source.DjangoConfigSourceTests.test_host_can_disable_global_rsync_bandwidth_limit src.pobsync_backend.tests.test_configure_commands.ConfigureCommandsTests.test_configure_host_uses_global_retention_defaults src.pobsync_backend.tests.test_run_scheduled_config_source.RunScheduledConfigSourceTests.test_dry_run_applies_configured_bandwidth_limit src.pobsync_backend.tests.test_run_scheduled_config_source.RunScheduledConfigSourceTests.test_real_run_can_request_verbose_output_args --verbosity 2`
- `.venv/bin/python manage.py test src.pobsync_backend.tests.test_views.ViewTests.test_create_host_config_form_creates_host src.pobsync_backend.tests.test_views.ViewTests.test_host_detail_renders_effective_config_preview src.pobsync_backend.tests.test_views.ViewTests.test_run_detail_renders_result_payload src.pobsync_backend.tests.test_views.ViewTests.test_host_config_form_updates_host_config --verbosity 2`
- `.venv/bin/python manage.py check`

Closes #51

src/pobsync_backend/management/commands/configure_pobsync_host.py

@@ -22,6 +22,12 @@ class Command(BaseCommand):
         parser.add_argument("--exclude-add", action="append", default=[])
         parser.add_argument("--exclude-replace", action="append", default=None)
         parser.add_argument("--rsync-extra-arg", action="append", default=[])
+        parser.add_argument(
+            "--rsync-bwlimit-kbps",
+            type=int,
+            default=None,
+            help="Host rsync bandwidth limit in KB/s. Omit to inherit global; set 0 for unlimited.",
+        )
         parser.add_argument("--retention", default=None)
         parser.add_argument("--disabled", action="store_true")
         parser.add_argument("--force", action="store_true", help="Update existing host")
@@ -42,6 +48,7 @@ class Command(BaseCommand):
             "excludes_add": [] if options["exclude_replace"] is not None else list(options["exclude_add"]),
             "excludes_replace": options["exclude_replace"],
             "rsync_extra_args": list(options["rsync_extra_arg"]),
+            "rsync_bwlimit_kbps": options["rsync_bwlimit_kbps"],
             "retention_daily": retention["daily"],
             "retention_weekly": retention["weekly"],
             "retention_monthly": retention["monthly"],