Should I include user model in database schema? And how to handle users registering their business?

Let's clarify the approach:
1. Kinde and User Management:
No user model needed: Kinde handles user management (registration, login, etc.) and stores user data securely. You don't need to create a separate user model in your Convex database.
Accessing user information: You can access the currently logged-in user's information (e.g., user ID) within Convex functions using Kinde's provided methods or libraries.
2. Restaurant Model in Convex:
Create a Restaurant table: Define a Restaurant table in your Convex schema with relevant fields like:
name (string)
ownerId (string, referencing the Kinde user ID)
address (string)
otherRestaurantDetails (any additional information)
3. Linking Restaurants to Users:
When a user registers a restaurant:
Inside your Convex function handling restaurant registration, retrieve the currently logged-in user's ID using Kinde's methods.
Store this user ID in the ownerId field of the newly created restaurant record in the Restaurant table.
4. Access Control and Data Ownership:
Convex function authorization: Within your Convex functions, you can use the auth object to check the currently logged-in user and their permissions. This allows you to restrict access to restaurant data based on ownership (e.g., only the owner can modify a restaurant's information).
Example Flow:
User logs in using Kinde.
User fills out a form to register their restaurant.
The frontend sends a request to a Next.js API route.
The API route calls a Convex function to handle restaurant registration.
The Convex function:
Retrieves the logged-in user's ID from Kinde.
Creates a new record in the Restaurant table with the restaurant details and sets the ownerId to the retrieved user ID.