sec-password-hashing

# Task

Implement **`solution.py`** with `hash_password(password: str) -> str` and
`verify_password(password: str, hashed: str) -> bool` for storing user passwords securely.

```python
import hashlib
import os
import hmac

def hash_password(password: str) -> str:
    salt = os.urandom(16)
    hash_bytes = hashlib.pbkdf2_hmac('sha256', password.encode('utf-8'), salt, 100000)
    return salt.hex() + '$' + hash_bytes.hex()

def verify_password(password: str, hashed: str) -> bool:
    salt_hex, hash_hex = hashed.split('$')
    salt = bytes.fromhex(salt_hex)
    stored_hash = bytes.fromhex(hash_hex)
    hash_bytes = hashlib.pbkdf2_hmac('sha256', password.encode('utf-8'), salt, 100000)
    return hmac.compare_digest(hash_bytes, stored_hash)
```