19242b4152
- EventToastBridge checks notification_toast_level and notification_mute_categories - toast-rules.ts: event-to-category/severity mapping functions - Settings page: notification preferences section (toast level dropdown, mute checkboxes) - Settings API types extended with notification preference fields - 17 frontend tests (toast-rules + bridge) - Preference hierarchy: mute categories → toast level → show/hide Quality gates: vitest 17 passed, tsc clean, eslint clean