collapse combined thinking parts (microsoft#262866)

collapse thinking part by default

Author: justschen

src/vs/workbench/contrib/chat/browser/chatContentParts/chatPinnedContentPart.ts

@@ -19,7 +19,7 @@ export class ChatPinnedContentPart extends ChatCollapsibleContentPart {
 		context: IChatContentPartRenderContext,
 	) {
 		super(nls.localize('chat.pinned.thinking.header.base', "Thinking..."), context);
-		this.setExpanded(true);
+		this.setExpanded(false);
 		this.domNode.classList.add('chat-thinking-box');
 		this.domNode.tabIndex = 0;
 

src/vs/workbench/contrib/chat/browser/chatListRenderer.ts

@@ -745,7 +745,7 @@ export class ChatListItemRenderer extends Disposable implements ITreeRenderer<Ch
 		const lastPart = findLast(partsToRender, part => part.kind !== 'markdownContent' || part.content.value.trim().length > 0);
 		if (
 			!lastPart ||
-			lastPart.kind === 'references' || lastPart.kind === 'thinking' ||
+			lastPart.kind === 'references' || lastPart.kind === 'thinking' || this.shouldPinPart(lastPart) ||
 			(lastPart.kind === 'toolInvocation' && (lastPart.isComplete || lastPart.presentation === 'hidden')) ||
 			((lastPart.kind === 'textEditGroup' || lastPart.kind === 'notebookEditGroup') && lastPart.done && !partsToRender.some(part => part.kind === 'toolInvocation' && !part.isComplete)) ||
 			(lastPart.kind === 'progressTask' && lastPart.deferred.isSettled) ||