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/qs/lib/formats.js

@@ -0,0 +1,23 @@
+'use strict';
+
+var replace = String.prototype.replace;
+var percentTwenties = /%20/g;
+
+var Format = {
+    RFC1738: 'RFC1738',
+    RFC3986: 'RFC3986'
+};
+
+module.exports = {
+    'default': Format.RFC3986,
+    formatters: {
+        RFC1738: function (value) {
+            return replace.call(value, percentTwenties, '+');
+        },
+        RFC3986: function (value) {
+            return String(value);
+        }
+    },
+    RFC1738: Format.RFC1738,
+    RFC3986: Format.RFC3986
+};