Doodle-jump camera and remove player shadow

- Camera now uses a trigger line at 42% from top. Player rises/falls
  freely below the line; camera only scrolls up past it, never down.
- Remove playerShadow graphics that followed the hero around.
- Ignore .vercel-cli-config (CLI auth cache used as Windows workaround).

src/scenes/GameScene.js

@@ -41,9 +41,6 @@ export class GameScene extends Scene {
     this.player = new Player(this, GAME_WIDTH / 2, startY - 140);
     this.lastJumpY = this.player.y;
 
-    this.playerShadow = this.add.graphics();
-    this.playerShadow.setDepth(-4);
-
     this.effects = new EffectsManager(this);
 
     this.platformManager = new PlatformManager(this);
@@ -60,9 +57,9 @@ export class GameScene extends Scene {
     this.physics.add.overlap(this.player, this.platformManager.getEnemies(), this.handleEnemy, null, this);
 
     this.cameras.main.setBounds(0, -999999, GAME_WIDTH, 999999 + GAME_HEIGHT);
-    // Manual upward-only follow: camera rises with player but never drops.
-    // Avoids lerp lag at high boost velocities that looked like FPS judder.
-    this.cameraOffsetY = 180;
+    // Doodle-jump camera: free movement below the trigger line, camera only
+    // scrolls up when player rises above it, and never moves down.
+    this.cameraTriggerY = GAME_HEIGHT * 0.42; // ~358 of 854 (just above middle)
     this.cameras.main.setRoundPixels(false);
 
     this.isGameOver = false;
@@ -86,10 +83,10 @@ export class GameScene extends Scene {
 
     this.player.update(this.cursors, this.wasd, this.touchLeft, this.touchRight, time, delta);
 
-    // Camera follow: instantly track player on the way up, never drop.
-    const targetY = this.player.y - GAME_HEIGHT / 2 + this.cameraOffsetY;
-    if (targetY < this.cameras.main.scrollY) {
-      this.cameras.main.scrollY = targetY;
+    // Camera: latch player at trigger line going up, free movement otherwise.
+    const targetScrollY = this.player.y - this.cameraTriggerY;
+    if (targetScrollY < this.cameras.main.scrollY) {
+      this.cameras.main.scrollY = targetScrollY;
     }
 
     this.bg.tilePositionY = Math.round(this.cameras.main.scrollY * 0.3);
@@ -116,18 +113,9 @@ export class GameScene extends Scene {
       this.lastJumpY = this.player.y;
     }
 
-    this.updatePlayerShadow();
     this.effects.update(this.player, delta);
   }
 
-  updatePlayerShadow() {
-    this.playerShadow.clear();
-    if (!this.player.active) return;
-    const alpha = Math.max(0.05, 0.25 - (Math.abs(this.player.body.velocity.y) / 1200));
-    this.playerShadow.fillStyle(0x000000, alpha);
-    this.playerShadow.fillCircle(this.player.x, this.player.y + 42, 16);
-  }
-
   platformCollisionFilter(player, platform) {
     if (!platform || !platform.body) return false;
     if (typeof platform.isBroken === 'function' && platform.isBroken()) return false;