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/abbrev/README.md

@@ -0,0 +1,23 @@
+# abbrev-js
+
+Just like [ruby's Abbrev](http://apidock.com/ruby/Abbrev).
+
+Usage:
+
+    var abbrev = require("abbrev");
+    abbrev("foo", "fool", "folding", "flop");
+    
+    // returns:
+    { fl: 'flop'
+    , flo: 'flop'
+    , flop: 'flop'
+    , fol: 'folding'
+    , fold: 'folding'
+    , foldi: 'folding'
+    , foldin: 'folding'
+    , folding: 'folding'
+    , foo: 'foo'
+    , fool: 'fool'
+    }
+
+This is handy for command-line scripts, or other cases where you want to be able to accept shorthands.