Create Signup Endpoint

[biniyam-29]

Develop an API endpoint to handle user registration for the application. This endpoint should receive a new user's details (e.g., username, email, password) and store them securely in the database. Ensure that passwords are hashed and sensitive data is properly validated and sanitized. Return appropriate success and error messages to indicate whether registration was successful or if any validation issues were encountered.

Requirements:

• Validate required fields (e.g., username, email, password).
• Hash passwords before storing them in the database.
• Check for existing accounts with the same email to prevent duplicate registrations.
• Return success message and user ID on successful signup.
• Return error messages for validation or duplicate account issues