feat(phase2): localization EN/RU + additional widget types

- Add svelte-i18n with 224 translation keys (English + Russian)
- Language switcher in header (EN/RU toggle, persists to localStorage)
- Extract all hardcoded strings from 37 component/page files
- Add 4 new widget types: Bookmark, Note (markdown), Embed (iframe), Status
- WidgetRenderer dispatches by type, WidgetGrid supports full-width widgets
- Type-specific config forms in board editor
- Install marked for markdown rendering

package.json

@@ -29,6 +29,7 @@
 		"clsx": "^2.1.0",
 		"jsonwebtoken": "^9.0.2",
 		"lucide-svelte": "^0.469.0",
+		"marked": "^17.0.5",
 		"node-cron": "^3.0.3",
 		"openid-client": "^6.8.2",
 		"simple-icons": "^13.0.0",
@@ -49,6 +50,7 @@
 		"@testing-library/svelte": "^5.2.0",
 		"@types/bcryptjs": "^2.4.6",
 		"@types/jsonwebtoken": "^9.0.7",
+		"@types/marked": "^6.0.0",
 		"@types/node-cron": "^3.0.11",
 		"eslint": "^9.18.0",
 		"eslint-config-prettier": "^10.0.0",