Prevent the need to uninstall extension to create new wallet

## Problem
If I want to create a fresh new wallet (seed phrase), I am forced uninstall and reinstall the extension.

Where I'd expect to be able to create a **new wallet** (but can't) is in the lock screen.

When I log out of my installed version, I only get two options:
- Log in
- Restore/import from seed phrase

## Solution
We should add a third option which is to **Create new wallet** to prevent the need to uninstall and reinstall the extension.

### Design suggestion
Add option to the lock screen to **start over**.

EDIT: If the user clicks on **Create new wallet** option, show a warning pop up that says **"Are you sure you want to Create a new wallet? This will reset your wallet and you will not be able to log in the current account.**" Maybe even a 2nd step where the user needs to type a word like "Reset wallet" to make sure they understand the implication of starting over.

Then after warning messages, show this page as if it were a fresh new install.

I realize this might be more of developer feature so alternatively, I'd vouch for at least adding a secret keyboard command that puts me back as if it were a fresh install so that I don't have to go through the whole process of uninstalling and reinstalling the extension.

Start from the lock-screen flow, then inspect the existing logout, restore/import, and fresh-install onboarding paths. Confirm how wallet state is reset and where the warning is shown; done means a user can safely choose Create new wallet, acknowledge the warning, and reach the fresh-install flow without uninstalling the extension.

Written by the indexing model from the issue text.