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/minipass-flush/README.md

@@ -0,0 +1,47 @@
+# minipass-flush
+
+A Minipass stream that calls a flush function before emitting 'end'
+
+## USAGE
+
+```js
+const Flush = require('minipass-flush')
+cons f = new Flush({
+  flush (cb) {
+    // call the cb when done, or return a promise
+    // the 'end' event will wait for it, along with
+    // close, finish, and prefinish.
+    // call the cb with an error, or return a rejecting
+    // promise to emit 'error' instead of doing the 'end'
+    return rerouteAllEncryptions().then(() => clearAllChannels())
+  },
+  // all other minipass options accepted as well
+})
+
+someDataSource.pipe(f).on('end', () => {
+  // proper flushing has been accomplished
+})
+
+// Or as a subclass implementing a 'flush' method:
+class MyFlush extends Flush {
+  flush (cb) {
+    // old fashioned callback style!
+    rerouteAllEncryptions(er => {
+      if (er)
+        return cb(er)
+      clearAllChannels(er => {
+        if (er)
+          cb(er)
+        cb()
+      })
+    })
+  }
+}
+```
+
+That's about it.
+
+If your `flush` method doesn't have to do anything asynchronous, then it's
+better to call the callback right away in this tick, rather than returning
+`Promise.resolve()`, so that the `end` event can happen as soon as
+possible.