[Feature]: Browser extension / PWA autofill for the password manager

[DenizAltunkapan]

Problem

Today passwords can only be used by copy-pasting from the web UI. The natural next step for a password manager is autofill directly in the browser.

Proposed solution

Two complementary directions:

• PWA + autofill in the existing frontend (installable app, Credential Management / Web OTP) — stays in this repo.
• Browser extension (Manifest V3, Chrome/Firefox) for real autofill on any site.

Open question — repo layout

The extension has its own build, store release cycle and security model, so it's probably better as a separate repo (e.g. password-manager-extension), with the vault crypto shared as a small package so we don't end up with two implementations. The PWA/autofill part stays here. Worth deciding before we start.

Acceptance criteria

• Decision documented: separate extension repo vs. in-repo
• Autofill works for login forms on real sites
• Vault crypto is shared, not duplicated, between web app and extension