Infra: Enable sonar for frontend

[Haarolean]

Despite the new (?) sonarcloud feature to do an automatic analysis without CI (github in our case) for all the languages in the repo the results for the frontend are ignored. We need to fix that.

https://sonarcloud.io/project/activity?id=kafbat_kafka-ui

[timwehrle]

@Haarolean I can look into it.

[sh3hz]

Is this a limitation for automatic analysis? link to docs

[Haarolean]

Is this a limitation for automatic analysis? link to docs

it seems, perhaps! I guess we'd need a workflow to scan frontend package separately.