Task Management React App

I want a task management app with a React frontend and an Express backend.
Set up the frontend with React 18, Vite, and Tailwind in a client folder,
and the backend with Express in a server folder. When I run the frontend in
development, it should send all requests that start with /api to the backend.
Get both running so I can open the app in the browser and it can talk to the backend.

Add these backend endpoints. First, when someone asks for a login code: create
a random 6-digit code, save it temporarily, and use SuprSend to send them an
email with that code (the same "login code" workflow we set up in the dashboard).
In development you can optionally return the code in the response so we can test
without checking email. Second, when someone enters the code: check it against
what we saved, and if it's correct, create or update their profile in SuprSend
with their name and email so we can send them notifications. Third, add an
endpoint the frontend can call to tell SuprSend when a task was created, when
its status changed (e.g. moved to another column), or when it was deleted-so
SuprSend can send the right emails and in-app notifications. Keep all SuprSend
keys only on the backend. Clean and validate every input (email, name, code) and
use a secure random generator for the 6-digit code.

On the login page, do a two-step flow. Step one: the user types their name and
email and clicks something like "Send code." The app calls the backend to send
the 6-digit code to their email. Step two: they type the code they received and
click "Verify and sign in." The app checks the code with the backend, then
signs them in and takes them to the task board. No demo or skip option-only
this email code login. For the main app, use a layout with a sidebar on the left
that shows the user's name and email, links to "Task Board" and "Notification
Preferences," and a Sign out button. The rest of the screen shows whichever page
they're on. Use Tailwind and Lucide icons for styling.

Add a task board with four columns: To Do, In Progress, In Review, and Completed.
Users can drag tasks between columns. Each task has a title, description, priority
(low, medium, high), and due date. They can add, edit, and delete tasks in a popup
modal. Save tasks per user in the browser (localStorage) so they persist. When
someone creates a task, tell the backend so it can send a "task created"
notification. When they move a task to another column, tell the backend so it
can send a "status changed" notification. When they delete a task, tell the
backend so it can send a "task deleted" notification (use whatever workflow we
set up for that in SuprSend). Show priority with a colored left border (e.g. red
for high, yellow for medium, green for low). Important: define the column component
in the same file as the board; don't create a separate file for it or you'll get
a duplicate error.

Add the SuprSend React package to the frontend. When the user is logged in and
we've added the SuprSend public key (from the dashboard) to the app's environment,
wrap the app in whatever SuprSend needs so it can show notifications and the
preferences page later. If the key isn't set or the user isn't logged in, just
show the app as usual without the notification features. Don't add the bell or
the preferences page yet-only this connection step.

Add SuprSend's drop-in inbox (the bell with popover feed) next to the "New task"
button on the task board page.

Show a toast when a new notification arrives. The SuprSend React SDK exposes a
feed event for new notifications (feed.new_notification). Inside the Inbox tree,
listen for that event on the feed client. When it fires, show a toast using your
toast library (e.g. react-hot-toast) and render SuprSend's ToastNotificationCard
with the notification data. Optionally mark the notification as seen. Clean up
the listener on unmount.

Add a page called "Notification Preferences" and put a link to it in the sidebar.
On this page, show the notification types we set up in SuprSend-like when a task
is created, when a task is updated, and when a task is deleted. For each type,
let the user turn it on or off and choose whether they want to get it by email
and/or in the app (the bell). Use toggle switches. When the SuprSend public key
isn't in the app, show a short message that preferences aren't available instead
of loading anything from SuprSend.

Make the whole app use a light theme-light gray or white backgrounds and dark
text everywhere: the main area, sidebar, login screen, task board, task cards,
the task popup, the preferences page, and any error screen. Also add a simple
error boundary: if something breaks in the app, show a friendly error message and
a "Try again" button instead of a blank or broken screen.