Implement CSV/JSON import and export for domains, notification groups and tags (with masking for sensitive channel data), including size/format validation, in-memory CSV building, and logging. Add tag transfer and bulk transfer actions (admin-only). Introduce a new update system: Add UpdateController and UpdateService, migration 025_add_update_system_v1.1.3.sql, and installer changes to include the new migration and version handling; provide endpoints to check, apply, rollback and configure updates. Update helpers and UI bits: add getUpdateBadgeInfo in LayoutHelper, update notification icons/redirects, and add getMaxUploadSize in ViewHelper. Misc: add NotificationGroup::findByName, tweak .gitignore backups path, and update related views and routes.
Refactored error log model and views to use a unified 'notes' field instead of 'resolution_notes'. Added a modal dialog for entering resolution notes when marking errors as resolved in admin views. Improved stack trace handling in ErrorHandler by storing as JSON and formatting for display. Expanded NotificationService to support multi-channel notifications (email, Telegram, Discord, Slack), group notifications, and improved domain expiration alerts.
Introduces error log tracking with new ErrorLog model, controller, views, and migration. Adds admin UI for viewing, resolving, and deleting errors. Implements bulk actions for users and notification groups, refactors domain filtering/pagination, and centralizes admin access checks using Auth::requireAdmin().
