E-Commerce Product Page with Cart Functionality

Build a dynamic e-commerce product page where users can:

- View a list of products fetched from a mock API (e.g., FakeStoreAPI or a JSON file).
- Add products to a cart with a button.
- Remove products from the cart from both the product listing and cart preview.
- See a floating cart preview that updates in real-time when items are added or removed.
- Use localStorage to persist the cart items across page reloads.
- Quantity Selector: Allow users to increase/decrease item quantity inside the cart.
- Total Price Calculation: Display the total cost of items in the cart.
- Toast Notifications: Show a small alert (e.g., "Item added to cart") when a product is added.

Requirements & Technologies
React: Use functional components and hooks (useState, useEffect).
Tailwind CSS: Style the product grid, buttons, and floating cart using Tailwind’s utility classes.
LocalStorage: Store cart data so that users don’t lose their cart on refresh.
Mock API (FakeStoreAPI or JSON file): Fetch product data dynamically instead of hardcoding it.