Add defensiveness against missing language for recommendations

[bjester]

Summary

• Ensures we only show the recommendations iff we have a valid request
• Adds defensive route guard that ensures currentChannel is loaded, which is used for recommendation request's fallback language
• Updates le-utils to latest version, which includes schema changes, and corresponding changes implemented

References

fixes #5111

Reviewer guidance

1. Have a public channel from production, such as KA, imported into your local instance
2. Open a new channel, and create a folder hierarchy for recommendations, e.g. Elementary > Math > Algebra
3. Open the destination folder (e.g. Algebra)
4. Click ADD, then 'Import from channels'
5. Verify recommendations show
6. Refresh the page with the import modal open
7. Verify recommendations appear again

[bjester]

⚠️ Requires that we merge this first, or otherwise break recommendations on unstable

[akolson]

Code changes make sense to me. Thanks @bjester