Add new project: Flappy Bird Game

### Project slug (e.g., snake, todo)

flappy-bird

### Summary

Page / Component: projects/FlappyBird (new project)

Description:
Implement a Flappy Bird clone game where the player controls a bird navigating through moving pipes. The player taps or presses a key to keep the bird airborne while avoiding obstacles. The game should include smooth animations, scoring, restart options

### Details / Acceptance criteria

Player can control the bird with tap/spacebar to “flap.”

Pipes move continuously from right to left at increasing speed.

Collision detection implemented for pipes and ground.

Score increments each time the bird passes through pipes.

Game Over screen with restart and high score display.

Add sound effects (flap, score, crash).

Responsive layout for desktop and mobile.

### Scope

- [x] UI changes
- [x] Logic changes
- [x] Accessibility
- [x] Tests (manual)