Fire weapons

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

lib/features/player/weapons/knife.dart

@@ -0,0 +1,24 @@
+import 'package:wolf_dart/features/player/weapon.dart';
+
+class Knife extends Weapon {
+  Knife()
+    : super(
+        name: "Knife",
+        idleSprite: 416,
+        fireFrames: [417, 418, 419],
+        damage: 15,
+        msPerFrame: 120,
+      );
+
+  @override
+  bool fire(int currentTime, {required int currentAmmo}) {
+    // Knife doesn't need ammo!
+    if (state == WeaponState.idle) {
+      state = WeaponState.firing;
+      frameIndex = 0;
+      lastFrameTime = currentTime;
+      return true;
+    }
+    return false;
+  }
+}