Feature Request: Add "Unlock PDF" (Remove Password) utility

[Adinath-j]

@JhaSourav07
The repository currently features a LockPdf page, but lacks the inverse utility. Users frequently need to remove passwords from PDFs they own for easier sharing or printing.

1. Proposed Solution:

2. Create a new route and page component /pages/UnlockPdf.
3. Implement a UI that allows users to upload a locked PDF and prompts them for the current password.
4. Use the underlying PDF service (src/services/pdf.service.js) to decrypt the document using the provided password and export a new, password-free version.

label suggestion: nsoc'26, enhancement, feature

count on me to implement this feature and assign it to me.

[JhaSourav07]

@Adinath-j

Assigned