chore(compass-assistant): add clear chat button COMPASS-9731

[gagik]

Adds chat clearing to the Assistant drawer:

[Copilot]

Pull Request Overview

This PR adds a clear chat button to the MongoDB Assistant drawer that allows users to delete all messages from the current chat session with a confirmation dialog.

• Added a clearChat action to the AssistantActionsContext that clears all messages from the chat
• Implemented a clear chat button in the drawer header with confirmation modal
• Added comprehensive tests for both confirmation and cancellation scenarios

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
compass-assistant-provider.tsx	Adds clearChat action to context that empties the chat messages array
compass-assistant-provider.spec.tsx	Adds test coverage for clear chat functionality with confirmation and cancellation flows
compass-assistant-drawer.tsx	Implements clear chat button in drawer header with confirmation dialog

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[Copilot]

Direct mutation of the chat.messages array may not trigger re-renders in React components that depend on this data. Consider using a proper state update method or immutable update pattern to ensure components re-render when messages are cleared.

Suggested change

	chat.messages = [];
	if (typeof chat.setMessages === 'function') {
	chat.setMessages([]);
	} else if (typeof chat.clearMessages === 'function') {
	chat.clearMessages();
	} else {
	// Fallback: do nothing or log a warning
	console.warn('No method to clear chat messages found.');
	}

[gagik]

It will, this is a ai-sdk thing

[lerouxb]

compass/packages/compass-assistant/src/vendor/@ai-sdk/react/chat-react.ts

Lines 60 to 63 in d1c9738

	set messages(newMessages: UI_MESSAGE[]) {
	this.#messages = [...newMessages];
	this.#callMessagesCallbacks();
	}