Code-server: Wish adding an icon to show the connection status with the server

[phoenixsfly]

While I was writing code, my computer was disconnected from the server for some reason, but I didn't know.
I pressed Ctrl+S to save the file and close the browser, but there was no doubt the file wasn't saved -- I had no idea I was disconnected from the server.
So I wanted to be able to add an icon to show the status of the browser's communication with the server.
Thank you very much!

[sr229]

Actually in Theia, the status bar changes color and adds a "Offline" in the left of the status bar. I think we can implement that but we wanna be close to the VSCode upstream as possible in v2.

[sr229]

@code-asher Actually I think we can use the VSCode Remote status used in the status bar for this, wdyt?

[code-asher]

VS Code web ended up adding an indicator before we did. It's in latest master and there will be another pre-release soon. They implemented it as a full-screen notification so there's no missing it.