[FEATURE] Add Environment Variables Validation on Server Startup

[Vidheendu]

Is your feature request related to a problem? Please describe.

If required environment variables are missing or incorrectly configured, the server may fail unexpectedly or throw unclear runtime errors. This can make setup difficult for new contributors and developers.

Describe the solution you'd like

Add a startup validation system that checks whether all required environment variables are present before the server starts.

Suggested improvements:

• Validate required .env variables
• Show clear error messages for missing variables
• Stop server startup if critical variables are absent
• Keep implementation lightweight and easy to maintain

Example:

• MONGO_URI missing
• JWT_SECRET missing

Describe alternatives you've considered

Currently, missing variables may only be discovered when a related feature breaks. Early validation would improve the developer experience and debugging process.

Additional Context

This would be a beginner-friendly backend improvement and helpful for contributors setting up the project locally.

[Vidheendu]

/assign

[yash-pouranik]

As I remember 2 months back I alreadyy added checks to check for env vars?
u can check in app.js or somewhere else
if they are not really help full then let me know what is actually worng in the code base by pointing to it.
then only I can assign this to you.
@Vidheendu