feat: person excludes for auto-organize rules, backup & restore system

Add person exclude criteria to Immich auto-organize — assets containing
excluded persons are filtered out after candidate gathering. Also adds
full backup/restore system with export, import, scheduled backups, and
retention management.

frontend/src/routes/+layout.svelte

@@ -193,6 +193,7 @@
 				key: 'nav.settings', icon: 'mdiCogOutline',
 				children: [
 					{ href: '/settings', key: 'nav.common', icon: 'mdiCogOutline' },
+					{ href: '/settings/backup', key: 'nav.backup', icon: 'mdiBackupRestore' },
 					{ href: '/users', key: 'nav.users', icon: 'mdiAccountGroup' },
 				],
 			},
@@ -236,6 +237,7 @@
 		{ href: '/command-template-configs', key: 'nav.templates', icon: 'mdiCodeBracesBox' },
 		...(auth.isAdmin ? [
 			{ href: '/settings', key: 'nav.settings', icon: 'mdiCogOutline' },
+			{ href: '/settings/backup', key: 'nav.backup', icon: 'mdiBackupRestore' },
 			{ href: '/users', key: 'nav.users', icon: 'mdiAccountGroup' },
 		] : []),
 	]);