Minecraft 8

Replace the current mouse-drag camera rotation with proper Pointer Lock controls. When the user clicks on the canvas, call requestPointerLock() to capture the cursor. While pointer lock is active, use movementX / movementY from mousemove events to rotate the camera yaw and pitch continuously — no click-and-drag needed. Hide the crosshair and show a "Click to play" overlay when pointer lock is not active; once locked, show the crosshair and hide the overlay. Handle pointerlockchange and pointerlockerror events properly. Press Escape to release pointer lock (this is handled natively by the browser). Left click and right click for block placement / removal should only work while pointer lock is active.