feat: add email subscription modal

[eliobricenov]

<--- Put the description here --->

The modal will show after the user finishes the onboarding.

How to test:

• import a MM wallet or connect MM mobile or wallet connect

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Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)

[eliobricenov]

A good portion of the component is similar to the AuthModal component but I wanted to decouple them so we have more control over it. By using a different electron partition we also make sure that we get the same layout even if the user logs in, which is not the case if we use the AuthModal.

[nyghtstalker]

Works great!

[BrettCleary]

works great for me

let's add an .env.example file with the LD flag

[BrettCleary]

Tested again and it works great for me!