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-addon-api/except.gypi

@@ -0,0 +1,25 @@
+{
+  'defines': [ 'NAPI_CPP_EXCEPTIONS' ],
+  'cflags!': [ '-fno-exceptions' ],
+  'cflags_cc!': [ '-fno-exceptions' ],
+  'conditions': [
+    ["OS=='win'", {
+      "defines": [
+        "_HAS_EXCEPTIONS=1"
+      ],
+      "msvs_settings": {
+        "VCCLCompilerTool": {
+          "ExceptionHandling": 1,
+          'EnablePREfast': 'true',
+        },
+      },
+    }],
+    ["OS=='mac'", {
+      'xcode_settings': {
+        'GCC_ENABLE_CPP_EXCEPTIONS': 'YES',
+        'CLANG_CXX_LIBRARY': 'libc++',
+        'MACOSX_DEPLOYMENT_TARGET': '10.7',
+      },
+    }],
+  ],
+}