## Summary The app starts silently even when required env vars are missing. Add startup validation. ## Acceptance Criteria - [ ] Install `@nestjs/config` and `joi` - [ ] `ConfigModule.forRoot` with a Joi schema validating: `DATABASE_URL`, `JWT_SECRET`, `STELLAR_NETWORK`, `PORT` (default 4000) - [ ] App fails fast with a clear error message if any required var is missing - [ ] `.env.example` updated with all required keys and descriptions
Summary
The app starts silently even when required env vars are missing. Add startup validation.
Acceptance Criteria
@nestjs/configandjoiConfigModule.forRootwith a Joi schema validating:DATABASE_URL,JWT_SECRET,STELLAR_NETWORK,PORT(default 4000).env.exampleupdated with all required keys and descriptions