feat: implement post-authentication redirect via redirect_after_login parameter

[Arav-Menon]

When someone shares a link to join a room or community they usually get sent to the page after they log in. Then they have to find their way to where they wanted to go. This change makes it easier for people to get to where they want to go.

The solution is to add something called redirect_after_login to the login and register pages. When someone uses this the app will automatically send them to the place after they log in or register.

Here are the main things that changed:

• I added redirect_after_login to the search parameters for login and register pages.

• I made it so the app checks for this parameter soon as someone starts logging in.

• I made sure the redirect_after_login parameter is not lost when people switch between the login and register pages.

• I used something called afterLoginRedirectPath to store where the person wants to go. It is not forgotten during the login process.

To test this you can do the following:

1. Make a link to the login. Register page, with the redirect parameter:

http://localhost:3000/#/login?redirect_after_login=%23%2Fhome%2Froom%2F!roomid%3Aexample.com

2. Log in. Register.

3. Check that the app sends you to the room you wanted to go to after you log in.

[github-actions]

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