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/sqlite3/deps/common-sqlite.gypi

@@ -0,0 +1,60 @@
+{
+  'variables': {
+      'sqlite_version%':'3440200',
+      "toolset%":'',
+  },
+  'target_defaults': {
+    'default_configuration': 'Release',
+    'conditions': [
+      [ 'toolset!=""', {
+        'msbuild_toolset':'<(toolset)'
+      }]
+    ],
+    'configurations': {
+      'Debug': {
+        'defines!': [
+          'NDEBUG'
+        ],
+        'cflags_cc!': [
+          '-O3',
+          '-Os',
+          '-DNDEBUG'
+        ],
+        'xcode_settings': {
+          'OTHER_CPLUSPLUSFLAGS!': [
+            '-O3',
+            '-Os',
+            '-DDEBUG'
+          ],
+          'GCC_OPTIMIZATION_LEVEL': '0',
+          'GCC_GENERATE_DEBUGGING_SYMBOLS': 'YES'
+        },
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'ExceptionHandling': 1, # /EHsc
+          }
+        }
+      },
+      'Release': {
+        'defines': [
+          'NDEBUG'
+        ],
+        'xcode_settings': {
+          'OTHER_CPLUSPLUSFLAGS!': [
+            '-Os',
+            '-O2'
+          ],
+          'GCC_OPTIMIZATION_LEVEL': '3',
+          'GCC_GENERATE_DEBUGGING_SYMBOLS': 'NO',
+          'DEAD_CODE_STRIPPING': 'YES',
+          'GCC_INLINES_ARE_PRIVATE_EXTERN': 'YES'
+        },
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'ExceptionHandling': 1, # /EHsc
+          }
+        }
+      }
+    }
+  }
+}