[Test] Initialize tests

[AntGa]

Problem

Currently, there are no automated tests to verify the integration between our database and Prisma ORM. This gap makes it difficult to ensure that our Prisma queries and mutations work as expected, potentially leading to unnoticed database issues during development or in production.

We need to introduce a set of tests that confirm our database works correctly with Prisma and ensure that all queries and mutations perform as intended across various use cases.

Objectives

• Implement automated tests to verify database connectivity using Prisma.
• Test basic CRUD operations for all key models (e.g., User, Post, Order).
• Ensure that relational queries (e.g., fetching related data) work correctly.
• Test how Prisma handles edge cases, such as invalid data or failed connections.
• Ensure that all Prisma-generated queries are compatible with our database (e.g., PostgreSQL or MySQL).

Acceptance Criteria

• Prisma successfully connects to the database in the test environment.
• CRUD operations (Create, Read, Update, Delete) are tested for key models.
• Relational data queries (e.g., include and select clauses) return the expected results.
• Edge cases (e.g., missing or invalid data) are handled appropriately, and proper error messages are returned.
• All tests are passing in the CI pipeline and are reliable across multiple database instances.
• Documentation is updated to include instructions on running the Prisma tests.
• Pull request is reviewed and approved, and tests are integrated into the CI workflow.