feat: add phone field to User model and update authentication flow

- Added phone field to User model in Prisma schema and generated types.
- Updated backend authentication to include phone as an additional field.
- Implemented phone input in the signup form with validation.
- Created a new SignupPage component for user registration.
- Updated routing to include signup path and redirect authenticated users.
- Modified login page to reference Playzer and added link to signup.

apps/backend/src/generated/prisma/internal/prismaNamespace.ts

@@ -1648,6 +1648,7 @@ export const UserScalarFieldEnum = {
   email: 'email',
   emailVerified: 'emailVerified',
   image: 'image',
+  phone: 'phone',
   createdAt: 'createdAt',
   updatedAt: 'updatedAt',
   role: 'role'