Organize game files into their project directory and ensure proper build configuration

Moves all game source files and assets into the 'American-Identity-Project' directory and updates the manifest to point to the 'Display' class as the main entry point.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: f6819c21-e85d-45ac-acde-604db2cfa4fe
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Event-Id: a9500e48-7f68-408f-a5c6-28df9f59fe00
Replit-Helium-Checkpoint-Created: true

American-Identity-Project/InvisibleTile.java

@@ -0,0 +1,13 @@
+import java.awt.Graphics;
+import javax.swing.ImageIcon;
+
+public class InvisibleTile extends Tile {
+  public InvisibleTile(int x, int y, int w, int h) {
+    super(x, y, w, h, new ImageIcon("Sprites/Bricks/Brick.png"));
+  }
+
+  @Override
+  public void draw(Graphics g) {
+    // draw nothing
+  }
+}