Admin can log into the portal

[jonadavrivera]

User Story

Title:
As an admin, I want to log into the portal using my username and password, so that I can securely manage the platform.

Acceptance Criteria:

1. The admin can enter a valid username and password.
2. The system validates the admin credentials.
3. The admin is redirected to the admin dashboard after successful authentication.
4. An error message is displayed when the credentials are invalid.
5. Protected pages cannot be accessed without authentication.

Priority: High

Story Points: 3

Notes:

• Passwords must not be stored as plain text.
• Authentication errors must not reveal sensitive information.