unreliable test: E2E sends message

## Test Details

- Name of test: sends message
- OS of failure: E2E Linux
- VSCode version of failure (minimum/insider/stable): stable
- Link to failing run: https://github.com/aws/aws-toolkit-vscode/commit/997b3b73ef07249d093d909265e479a9d0c81426
- Link to failing test: https://github.com/aws/aws-toolkit-vscode/blob/997b3b73ef07249d093d909265e479a9d0c81426/packages/amazonq/test/e2e/amazonq/chat.test.ts#L66-L74

## Log of Test Failure

```
TypeError: Cannot read properties of undefined (reading 'type')
at Context. (test/e2e/amazonq/chat.test.ts:73:45)
```

## Additional Information

Read packages/amazonq/test/e2e/amazonq/chat.test.ts around lines 66-74 and inspect the linked failing run. Reproduce the E2E “sends message” test and trace why the value at line 73 is undefined; done means the test completes without the TypeError and remains reliable on E2E Linux.

Written by the indexing model from the issue text.