Android Time-Based Puzzle Game

I’m building a mobile-only puzzle game for Android in which every level is a race against the clock. Players will have a clear countdown, escalating difficulty, and a fast, satisfying restart loop that keeps them chasing better times.

Here’s what I need from you:
• A complete, publish-ready APK plus the full project source.
• Clean, touch-friendly controls, responsive UI, and a lightweight art style that performs smoothly across current Android devices.
• A modular level system so I can add or tweak timed stages later without rewriting core code—Unity, Godot, or any comparable engine that supports this is fine.
• Basic settings (sound/music toggle, pause, restart) and Google-Play-ready build settings.
• Brief documentation outlining the project structure and how to create additional levels.

I’ll provide the overall theme and sample puzzle ideas once we start; you handle coding, asset integration, and packaging. Stability, quick load times, and polish on the timer mechanic are essential.

When you reply, please outline your proposed toolset, development timeline, and links to any timed puzzle titles you’ve shipped before.