Adds CFG_<APP>_BACKUP_STRATEGY (default auto) so an app's backup strategy can
be overridden from its Advanced config tab, taking precedence over the global
default. Added to the 10 live-capable apps, so the dropdown's 'live' option only
appears where it actually works.
- backupResolveStrategy now checks the per-app override before the global value.
- backupAppLiveCapable / backupAppStrategyOptions expose capability + the valid
option set; predicate helpers hardened with explicit returns so they behave
identically with or without shell errexit.
- BACKUP_STRATEGY field mapping (select, advanced) renders the dropdown.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>
27ad517626
