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/node-gyp/gyp/AUTHORS

@@ -0,0 +1,16 @@
+# Names should be added to this file like so:
+# Name or Organization <email address>
+
+Google Inc. <*@google.com>
+Bloomberg Finance L.P. <*@bloomberg.net>
+IBM Inc. <*@*.ibm.com>
+Yandex LLC <*@yandex-team.ru>
+
+Steven Knight <knight@baldmt.com>
+Ryan Norton <rnorton10@gmail.com>
+David J. Sankel <david@sankelsoftware.com>
+Eric N. Vander Weele <ericvw@gmail.com>
+Tom Freudenberg <th.freudenberg@gmail.com>
+Julien Brianceau <jbriance@cisco.com>
+Refael Ackermann <refack@gmail.com>
+Ujjwal Sharma <ryzokuken@disroot.org>