add: functional riffle and inventory for bullets

Assets/Scripts/Player/Rifle.cs

@@ -0,0 +1,21 @@
+using UnityEngine;
+
+public class Rifle : Weapon
+{
+    public GameObject projectilePrefab;
+    public Transform spawnPosition;
+    public float fireRate = 3f;
+
+    [SerializeField] float currentDelay = 0;
+
+    public override void Shoot(bool keyDown, bool keyHold) {
+        if (keyHold && (fireRate == 0 || currentDelay >= 1 / fireRate) && GameController.i.ConsumeBullet(BulletType.Rifle)) {
+            Instantiate(projectilePrefab, spawnPosition.position, spawnPosition.rotation);
+            currentDelay = 0;
+        }
+    }
+
+    void Update() {
+        if (fireRate != 0) currentDelay = Mathf.Clamp(currentDelay += Time.deltaTime, 0, 1 / fireRate);
+    }
+}