i18n slice 1 release B: parity cases + fixtures captured from UNCONVERTED backup templates

backups_apps, backups_remote, backups_restore, backups_restore_wizard, backups_escrow,
tier2_config, recovery. Case completeness checked with the coverage probe on a trial conversion.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/web/i18n_parity_test.go

@@ -279,6 +279,7 @@ func i18nCases() []i18nCase {
 	}
 	// Slice 1 (R-556): one file of cases per release, each captured from its unconverted templates.
 	base = append(base, i18nCasesA()...)
+	base = append(base, i18nCasesB()...)
 	return base
 }