feat: add environment configuration validation using zod and dotenv

[Kmario19]

This pull request introduces significant updates to the environment configuration and initialization process. The changes mainly focus on validating environment variables using the zod library and improving the structure of the environment loading process.

Environment configuration and validation:

• src/config/environment.ts: Added a new module that uses zod to validate environment variables and ensure they have the correct types and default values. This module also loads the environment variables using dotenv.

Initialization process improvements:

• src/index.ts: Removed the direct use of dotenv and replaced it with the new loadEnvironment function from the environment configuration module. This change ensures environment variables are validated before being used.
• src/index.ts: Moved the PORT variable assignment inside the conditional block that checks if the environment is not 'test', ensuring the server only starts in non-test environments.

[Copilot]

Pull Request Overview

This pull request introduces environment variable validation using the zod library, streamlining the configuration initialization process. Key changes include:

• Introducing a new module (src/config/environment.ts) that validates environment variables using zod and dotenv.
• Refactoring src/index.ts to remove direct dotenv usage and employ the loadEnvironment function for validation.
• Moving the PORT assignment into the conditional block to ensure the server only starts outside of test environments.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/index.ts	Replaces dotenv usage with loadEnvironment and adjusts PORT assignment.
src/config/environment.ts	Implements environment variable validation using zod, throwing errors when invalid.