Add main menu, ghost enemy, and sword slash trail

web/src/Sword.ts

@@ -3,6 +3,7 @@ import { Weapon } from './Weapon';
 import { Player } from './Player';
 import { loadGLB } from './MeshLoader';
 import { playSound } from './SoundManager';
+import { SlashEffect, isInSlashArc } from './SwordTrail';
 
 export class Sword extends Weapon {
   private mixer: THREE.AnimationMixer | null = null;
@@ -97,18 +98,24 @@ export class Sword extends Weapon {
 
     const { game } = player;
 
+    // Aim direction: where the blob actually faces (toward the mouse point)
+    const aim = new THREE.Vector3()
+      .subVectors(game.groundPoint, player.body.position);
+    aim.y = 0;
+    if (aim.lengthSq() < 0.001) {
+      aim.set(0, 0, -1).applyQuaternion(player.body.quaternion);
+      aim.y = 0;
+    }
+    aim.normalize();
+
+    // Slash trail feedback
+    const slash = new SlashEffect(player.body.position, aim, game.scene);
+    game.slashEffects.push(slash);
+
     for (const enemy of game.enemies) {
       if (enemy.dead) continue;
-      const dist = enemy.body.position.distanceTo(player.body.position);
-      if (dist < 3) {
-        const toEnemy = new THREE.Vector3()
-          .subVectors(enemy.body.position, player.body.position).normalize();
-        const playerFwd = new THREE.Vector3(0, 0, 1);
-        playerFwd.applyQuaternion(player.body.quaternion);
-        const dot = playerFwd.dot(toEnemy);
-        if (dot > 0.3) {
-          enemy.takeDamage(50, game);
-        }
+      if (isInSlashArc(player.body.position, aim, enemy.body.position)) {
+        enemy.takeDamage(50, game);
       }
     }
   }