Add WebSocket Terminal support

[isc-bsaviano]

This PR adds support for for the new terminal endpoint added in Atelier API v7. It will be available in the next preview of IRIS 2023.2. See the new documentation included in this PR for how to start the terminal and what features it supports.

[gjsjohnmurray]

I look forward to trying this out as soon as a suitable 2023.2 preview becomes available.

[isc-bsaviano]

This can be tested with the 2nd 2023.2 developer preview kit (2023.2.0.201.0)

[daimor]

That's very interesting

[daimor]

Well,
The terminal thing itself looks good, looks working

But there are a few Issues

When connection is disable, it keeps showing in this add terminal menu

But, in the list of main commands shown only when any ObjectScript file is open, even if the connection is active

And in the project with a Python virtual environment, made with venv, VSCode activates this virtual environment when opened a new terminal. No idea if it can be configured somehow, probably it's just implemented a way, that it sends this command to any terminal.

to reproduce it,
create a new virtual environment in the project and switch to it, VSCode should notice a new environment and offer to switch to it

python -m venv venv
source venv/bin/activate

[isc-bsaviano]

@daimor The terminal.profiles contribution point doesn't take a when clause, so I can' hide it when there's no active connection. I could open a VS Code issue but I doubt it would be resolved before this PR is merged. The second image looks like a bug in whatever code sends that command. It should check that the terminal isn't an extension terminal before sending it. I'm not sure where you should report that.

[daimor]

well, ok then

[isc-bsaviano]

FYI reported the when clause issue: microsoft/vscode#183354

[gjsjohnmurray]

For the venv issue see microsoft/vscode-python#20562

[isc-bsaviano]

@gjsjohnmurray Do you have any feedback before I merge this?

[gjsjohnmurray]

Some comments made. I haven't yet had time to install a 2023.2 that I can actually test the terminal with.