SyntaxError: Failed to construct 'WebSocket': Failed to create a WebSocket: the provided URL is invalid.

## Error

```
Failed to construct 'WebSocket': Failed to create a WebSocket: the provided URL is invalid.
```

## Stack trace

```
../app/javascript/components/track/IterationSummary.tsx:29 in IterationSummaryWithWebsockets
div
../app/javascript/components/common/SolutionView.tsx:32 in SolutionView
Suspense
../node_modules/@sentry/react/src/errorboundary.tsx:101 in new ErrorBoundary
../node_modules/@tanstack/react-query/src/QueryClientProvider.tsx:30 in QueryClientProvider
```

## Tracking Details
- **Project**: exercism-js
- **Sentry**: [SyntaxError: Failed to construct 'WebSocket': Failed to create a WebSocket: the provided URL is invalid.](https://thalamus-ai.sentry.io/issues/105006419/)
- **Culprit**: new IterationChannel(app/javascript/channels/iterationChannel)
- **First seen:** Mar 19, 2026