Marketing Hub: RBAC, i18n (AR/EN), tasks overhaul, team/user merge, tutorial

Features:
- Full RBAC with 3 roles (superadmin/manager/contributor)
- Ownership tracking on posts, tasks, campaigns, projects
- Task system: assign to anyone, filter combobox, visibility scoping
- Team members merged into users table (single source of truth)
- Post thumbnails on kanban cards from attachments
- Publication link validation before publishing
- Interactive onboarding tutorial with Settings restart
- Full Arabic/English i18n with RTL layout support
- Language toggle in sidebar, IBM Plex Sans Arabic font
- Brand-based visibility filtering for non-superadmins
- Manager can only create contributors
- Profile completion flow for new users
- Cookie-based sessions (express-session + SQLite)

server/node_modules/@npmcli/fs/lib/fs.js

@@ -0,0 +1,8 @@
+const fs = require('fs')
+const promisify = require('@gar/promisify')
+
+// this module returns the core fs module wrapped in a proxy that promisifies
+// method calls within the getter. we keep it in a separate module so that the
+// overridden methods have a consistent way to get to promisified fs methods
+// without creating a circular dependency
+module.exports = promisify(fs)