Fix stun baton throwing and visual effect (#18777)

Content.Shared/Stunnable/SharedStunbatonSystem.cs

@@ -0,0 +1,24 @@
+using Content.Server.Stunnable.Components;
+using Content.Shared.Damage;
+using Content.Shared.Weapons.Melee.Events;
+
+namespace Content.Shared.Stunnable;
+
+public abstract class SharedStunbatonSystem : EntitySystem
+{
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<StunbatonComponent, GetMeleeDamageEvent>(OnGetMeleeDamage);
+    }
+
+    private void OnGetMeleeDamage(EntityUid uid, StunbatonComponent component, ref GetMeleeDamageEvent args)
+    {
+        if (!component.Activated)
+            return;
+
+        // Don't apply damage if it's activated; just do stamina damage.
+        args.Damage = new DamageSpecifier();
+    }
+}