Browser: Webview Changes

[cookiengineer]

The Webview/iframe must do requests in a different schema now. This needs to be changed, and the interactions with the UI have to be changed accordingly.

• Webview points now to /stealth/<tab.id>/<url> as a schema, without any flags.
• The refresh button needs to do a separate WebSocket API call that calls something like a Task download() mechanism behind the scenes, and refreshes the iframe when it was successful (and the URL is still matching).