Site query params to configure designer host container

[Diegorro98]

Description

This PR allows to apply different configurations to the designer at the site. These are the query params:

• hostApp: Use a number to stablish the host app in the designer. Ex: https://adaptivecards.io/designer?hostApp=1 would set the host app to Outlook Actionable Message.
• theme: By using a string with the name of the theme (case sensitive) you can set the theme of the host container. The possible values depends on the available options for the host app. Ex: https://adaptivecards.io/designer?hostApp=2&theme=Dark would set the theme to Dark on the Microsoft Teams host app.
• size: By using a string with the name of the size (case sensitive) you can set the size of the host container. The possible values depends on the available options for the host app. Ex: https://adaptivecards.io/designer?hostApp=8&size=Medium would set the size of the Widget host app to Medium.
• deviceEmulation: By using a number, the device emulation can be set. Ex: Ex: https://adaptivecards.io/designer?hostApp=1&deviceEmulation=2 would set the emulation device to Large mobile (414px) at the Outlook Actionable Message host app.

I also added a query param that allows to activate the preview mode on the designer by adding preview=1 to the url.

How Verified

I tested it by running a local server