feat(compass-assistant): handle assistant errors COMPASS-9695

[lerouxb]

This logs assistant errors like this:

{"t":{"$date":"2025-08-27T10:36:56.587Z"},"s":"E","c":"COMPASS-ASSISTANT","id":1001000370,"ctx":"Assistant","msg":"Failed to send a message","attr":{"err":{"message":"Failed to fetch"}}}

And it shows them in a banner like this:

Banner text is calculated as:

function makeErrorMessage(message: string) {
  message = message || 'An error occurred';
  return `${message}. Try clearing the chat if the error persists.`;
}

[Copilot]

Pull Request Overview

This PR implements error handling for the Assistant feature by adding logging capabilities and user-facing error notifications. The changes enable better debugging through structured logging and improve user experience by displaying error messages in a dismissible banner.

• Adds error logging to capture assistant failures with structured log messages
• Implements user-facing error notifications with a dismissible banner component
• Upgrades the AI SDK version to support enhanced error handling features

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

File	Description
packages/compass-assistant/src/compass-assistant-provider.tsx	Adds logger dependency and error callback to log assistant failures
packages/compass-assistant/src/assistant-chat.tsx	Implements error banner UI with dismissible functionality
packages/compass-assistant/src/@ai-sdk/react/use-chat.ts	Exposes clearError function from the chat interface
packages/compass-assistant/package.json	Updates AI SDK version from 5.0.5 to 5.0.26

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[gagik]

check is failing, otherwise LGTM