Add star rating display to game cards

[omerwein]

Description

Displays each game's star rating on the game cards using visual star graphics and a numerical score.

Changes

• Star graphics: Shows 5 stars with proportional filling to visualize the rating (e.g., 3.9/5 shows 3 full stars + 0.9 of the 4th star)
• Fallback text: Displays "No rating yet" when a game hasn't been rated
• Accessibility: Star SVGs are marked as aria-hidden="true" since the numerical rating conveys the information
• Styling: Yellow stars on gray background, positioned between the description and "View details" link

Testing

• ESLint: ✅ Passed
• Type checking: ✅ Passed (tsgo + astro check)
• E2E tests: ✅ All 21 tests passed, including accessibility checks

The implementation is small and focused—no layout restructuring, just a new section added to the card component using the existing starRating field from the Game type.