[Bug][Backend] Server startup fails because TWO_FACTOR_ENCRYPTION_KEY is missing from .env.example

[agarwalpranav0711]

Bug Summary

The backend authentication setup requires the environment variable TWO_FACTOR_ENCRYPTION_KEY, but this variable is not documented in backend/.env.example.

As a result, contributors following the documented setup process may encounter a startup failure because the required variable is never defined.

Steps to Reproduce

1. Clone the repository.
2. Copy backend/.env.example to backend/.env.
3. Follow the documented setup instructions.
4. Start the backend server.

Actual Behavior

The server fails to start because TWO_FACTOR_ENCRYPTION_KEY is required but not present in the example environment configuration.

Expected Behavior

All required environment variables should be documented in backend/.env.example so contributors can complete setup successfully.

Suggested Fix

Add the missing variable to backend/.env.example with a placeholder value and a short description of the required format.

Example:

TWO_FACTOR_ENCRYPTION_KEY=your_64_character_hex_key_here

Additional Context

This improves contributor onboarding and keeps the environment documentation aligned with the backend authentication requirements.

[agarwalpranav0711]

Hi maintainers,

I identified this setup/documentation issue while reviewing the backend configuration and would like to work on it.

Could you please assign this issue to me?

Thank you.

[agarwalpranav0711]

Hi maintainers,

I have submitted a fix for this issue.

PR: #1610

Thank you.