fix chat tip getting stuck when mode changes

[meganrogge]

fix #297287

[Copilot]

Pull request overview

Fixes the “getting started” chat tip widget getting stuck (showing only one tip with broken next/previous arrows) after switching chat modes (e.g., Local → Cloud) by ensuring the rendered tip is cleared when a new chat session/model is bound.

Changes:

• Clear any previously-rendered getting-started tip DOM + disposables when switching to a new chat model/session.
• Hide the tip container so the next empty-state render selects and renders a fresh, context-appropriate tip.

Comments suppressed due to low confidence (1)

src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts:2085

• This tip-clearing sequence is now duplicated in multiple places (config toggle handler, updateChatViewVisibility non-empty path, and here). Consider extracting a small private helper (e.g. clearGettingStartedTip()) to centralize the DOM + disposable cleanup and reduce the chance these paths drift over time.

		// Switching sessions resets tip service state; clear any rendered tip so
		// empty-state rendering picks a fresh, context-appropriate tip.
		this._gettingStartedTipPartRef = undefined;
		this._gettingStartedTipPart.clear();
		const tipContainer = this.inputPart.gettingStartedTipContainerElement;
		dom.clearNode(tipContainer);
		dom.setVisibility(false, tipContainer);