Add menu item for opening dedicated window

[jotaen4tinypilot]

Part of https://github.com/tiny-pilot/tinypilot/issues/728.

This PR adds an item to the “View” menu, which is labelled “Dedicated Window”, and which opens the remote screen in “standalone” view mode in a popup window.

https://github.com/tiny-pilot/tinypilot/assets/83721279/f6bdbdf5-5387-4f6a-8401-9b33f92fb5cb

Notes

• As discussed in this issue comment, we decided to use a rather pragmatic and slightly unconventional approach for hiding the remote screen from the main (parent) window, by issuing an external redirect to a separate page. A “clean” and proper teardown mechanism, which would allow us to stay on the main page, would probably be rather complex to build, and also brittle to maintain.
• I’ve debated whether to use an btn-action (blue) or a btn-success (green) for the “Refresh Page” button. I eventually went with the former, since the action is optional, and the button is only a convenience.

[mtlynch]

Lol, is this you?

Huh? Was this comment meant to go somewhere else or am I missing something?

[jdeanwallace]

Huh? Was this comment meant to go somewhere else or am I missing something?

Oh sorry, looks like GitHub doesn't like my gif. Only shows up in codeapprove:

[mtlynch]

Oh, haha, that makes more sense.

[jotaen4tinypilot]

Lol, is this you?

I wish, but I’m rather more like