Fix LSP connection error notification on restart

[lionel-]

Closes #7593

@midleman @rodrigosf672 Could you please see if this branch fixes your skipped tests?

I think the notification is due to our closed() handler (

positron/extensions/positron-r/src/error-handler.ts

Lines 40 to 43 in a767974

	public closed(): CloseHandlerResult {
	LOGGER.warn(`ARK (R ${this._version}) language client was closed unexpectedly (port ${this._port}).`);
	return { action: CloseAction.DoNotRestart, handled: true };
	}

) not being called when the client is already stopping: https://github.com/lionel-/vscode-languageserver-node/blob/f5e23e29b76c42fad882aa84933d46ba9b412183/client/src/common/client.ts#L1827-L1833. This prevents our handler from setting handled to true.

To work around this, we hook into the client's error handler to manually ignore these errors.

Release Notes

New Features

• N/A

Bug Fixes

• N/A

Validation Steps

Verified manually on my Linux laptop.

@:ark @:web

[github-actions]

E2E Tests 🚀
This PR will run tests tagged with: @:critical @:ark @:web

^{readme  valid tags}

[midleman]

@lionel- i just unskipped the test and added the web test tag in PR description to either confirm or deny the test is happy. 🤞

[rodrigosf672]

@lionel-, I'm pulling this change into my branch and will see if my (unskipped) test is happy as well. Thank you!

[lionel-]

Upstream fix: microsoft/vscode-languageserver-node#1782