[UX] Remember last url opened in the webview, reopen there

[arielj]

This PR fixes #758

Now the last url that we navigate to in the webview is remembered and used when clicking the stores icon in the sidebar.

Users can still navigate to any of the stores with the sidebar submenu or the game's Store page links.

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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)

[flavioislima]

Tested here and works just fine, except for the item on the sidebar that it is not changing based on the URL, I mean, it does not show as selected:

[flavioislima]

Another idea that could improve this would be to store the last URL per store instead of the whole webview.
This is useful when we are getting the free games from Amazon prime that sometimes includes GOG games that requires going to the GOG store and redeem the code.

[arielj]

@flavioislima can you check again? I updated the code to show the current store in the sidebar and to store the last url for each store independently

[flavioislima]

@flavioislima can you check again? I updated the code to show the current store in the sidebar and to store the last url for each store independently

I will check earlier in the morning! 👍

[flavioislima]

Works amazingly well now! :D