v2.7 — Leaderboard, Nicknames & Share

🏆 Firebase Leaderboard

• Compete for best solve time on each grid size and difficulty
• Rolling 7-day window — your score stays on the board for a full week
• Top 10 shown with medals 🥇🥈🥉

🎲 Shared Nickname System

• Pick a nickname (or roll a random one) — it's shared across all constrik games
• Your nick is highlighted in the leaderboard with ◀

📤 Share

• Share your result after solving — copies time, grid size and link to clipboard

🎮 Cross-Promotion

• Links to Open Office, Neighbors, HolePuncher, Ball Rush after each win

UI Fix

• New Game button aligned with settings dropdowns