fix: add bcrypt hashing and verification for police badge number in user controller

[Swapnxll]

This PR introduces the following changes to the user controller:

1. Hashing: Police badgeNumber is now securely hashed using bcrypt.js during registration.
2. Verification: badgeNumber is verified using bcrypt.compare() during login.

Fixes #30

Dependencies Added:

1. bcryptjs
2. jsonwebtoken

Why this is needed

1. To secure police credentials (badgeNumber) instead of storing them in plaintext.
2. To enable proper verification during login.

Setup:

npm install

Testing Steps

1. Register a police user with name and badgeNumber.
2. Attempt login with the same credentials.
3. A JWT token should be returned only if the badge number matches (hashed and verified properly).