Improve final winner display after full game

[Hartwich]

Goal

Improve Schaetzorama final winner display after the full game.

Codex Auftrag

Make the end screen clearer and more rewarding.

Focus

• clearly show final winner
• show final ranking
• show final scores
• make the end screen feel more rewarding

Acceptance Criteria

• Final winner is obvious.
• Ranking and scores are readable.
• End screen works for different player counts.
• npm run typecheck passes.
• npm run build passes.

Safety

Do not add copyrighted, unclear, or unreviewed third-party assets or content.