88 fetch top 5 games to display on the home page and create state for displaying comments

[johagber]

Summary

Replaces the mock data in the "Top rated games" section with real data. The top 5 games now come from the backend, link to their details pages, and the review panel shows real community reviews for whichever game is selected.

Closes #88

Changes

• New topGames(limit) GraphQL query that returns the highest rated games, using ratings count as a tiebreaker (the limit is clamped to 1–20)
• Added ratings_count to GameSummary in the GraphQL schema
• The reviews query now takes an optional limit, and fetchGameReviews passes it on, so the review panel can show just the latest few reviews
• New fetchTopGames API function, plus gameQueryOptions.top and gameReviewQueryOptions.latestByGameId query options
• Top5Games uses real data, with loading, error and empty states, and every list item links to the game's details page
• The game shown in the review panel is picked on hover or focus. On touch screens, where hover doesn't work, each item gets a review button instead
• ReviewPanel takes the selected game as a prop and shows its name, rating and latest 5 reviews, with loading, error and empty states
• The review panel remounts when the selected game changes, and autoscroll now waits a moment before it starts, so new reviews don't scroll off right away
• The seed script gives each of the top 5 games a review from every seeded user, with longer, more realistic texts, so the panel has something to show

Notes

• Run the seed script again to get the new reviews for the top 5 games.

[tobiaheg]

lgtm

[tobiaheg]

lgtm