feat: add DB schema, Postman collection, README & demo screenshots (Abrar Kivande)

[AbrarKivande]

Summary

• Added DB schema & seed file: server/sql/db_schema_fixed.sql
• Added Postman collection: server/sql/CabBooking.postman_collection.json
• Added README.md with run steps
• Added demo screenshots in AbrarKivande/ showing local run and UI add/delete
• Created .env.example and .gitignore

How to run locally (for reviewer)

1. Create cab_booking DB in pgAdmin4 and run server/sql/db_schema_fixed.sql.
2. In server, copy .env.example → .env and set PGPASSWORD.
3. Start the server:
   cd server
   npm install
   node index.js
4. Start the client:
   cd client
   npm install
   npm start
5. Verify: Visit http://localhost:3000 and test Add/Delete for Route and Schedule.

Demo screenshots

Included in AbrarKivande/:

Please review — I’m happy to make any small changes you request.