clarify auto-pause message and hide framing line during gameplay

Show "PAUSED — I can't see you! Step back into frame." when the
game auto-pauses. Hide the red framing line once the game has
started so only the pause message appears.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/pages/GamePage.tsx

@@ -169,7 +169,7 @@ export function GamePage() {
       <canvas ref={canvasRef} className="pose-overlay" />
       <canvas ref={arCanvasRef} className="ar-overlay" />
 
-      {(calibrationStatus === 'framing' || calibrationStatus === 'paused') && (
+      {!gameStarted && (calibrationStatus === 'framing' || calibrationStatus === 'paused') && (
         <div className="framing-line" />
       )}
 
@@ -182,7 +182,7 @@ export function GamePage() {
       )}
       {autoPaused && (
         <div className="debug-status">
-          I lost track of you — step back into frame!
+          PAUSED — I can't see you! Step back into frame.
         </div>
       )}