Implement Fort Fight minigame (#75)

Co-authored-by: Michal Pikulski <michal.a.pikulski@gmail.com>
Reviewed-on: #75

Assets/Scripts/Minigames/FortFight/Projectiles/TrashBagProjectile.cs

@@ -0,0 +1,107 @@
+using Core;
+using UnityEngine;
+
+namespace Minigames.FortFight.Projectiles
+{
+    /// <summary>
+    /// Trash Bag projectile - splits into multiple smaller pieces on impact.
+    /// Deals AOE damage in a forward cone.
+    /// </summary>
+    public class TrashBagProjectile : ProjectileBase
+    {
+        [Header("Trash Bag Specific")]
+        [Tooltip("Prefab for individual trash pieces (small debris)")]
+        [SerializeField] private GameObject trashPiecePrefab;
+        
+        protected override void OnHit(Collision2D collision)
+        {
+            // Deal initial damage from trash bag itself
+            var block = collision.gameObject.GetComponent<Fort.FortBlock>();
+            if (block != null)
+            {
+                block.TakeDamage(Damage);
+                Logging.Debug($"[TrashBagProjectile] Dealt {Damage} damage to {block.gameObject.name}");
+            }
+            
+            // Get settings for trash pieces
+            var settings = GameManager.GetSettingsObject<AppleHills.Core.Settings.IFortFightSettings>();
+            int pieceCount = settings?.TrashBagPieceCount ?? 8;
+            
+            Logging.Debug($"[TrashBagProjectile] Splitting into {pieceCount} pieces");
+            
+            // Get contact normal and impact point
+            Vector2 hitNormal = collision.contacts[0].normal;
+            Vector2 impactPoint = collision.contacts[0].point;
+            
+            // Spawn trash pieces (NOT parented, so they persist as debris)
+            SpawnTrashPieces(impactPoint, hitNormal);
+            
+            // Destroy trash bag after spawning pieces
+            DestroyProjectile();
+        }
+        
+        /// <summary>
+        /// Spawn multiple trash pieces in a cone away from the hit surface.
+        /// Uses hit normal + projectile momentum for realistic splash effect.
+        /// </summary>
+        private void SpawnTrashPieces(Vector2 impactPoint, Vector2 hitNormal)
+        {
+            if (trashPiecePrefab == null)
+            {
+                Logging.Warning("[TrashBagProjectile] No trash piece prefab assigned!");
+                return;
+            }
+            
+            // Get settings
+            var settings = GameManager.GetSettingsObject<AppleHills.Core.Settings.IFortFightSettings>();
+            int pieceCount = settings?.TrashBagPieceCount ?? 8;
+            float pieceForce = settings?.TrashBagPieceForce ?? 10f;
+            float spreadAngle = settings?.TrashBagSpreadAngle ?? 60f;
+            
+            // Calculate projectile's incoming direction (momentum)
+            Vector2 incomingDirection = rb2D.linearVelocity.normalized;
+            if (incomingDirection == Vector2.zero)
+            {
+                incomingDirection = LaunchDirection;
+            }
+            
+            // Calculate reflection direction from hit normal
+            // This creates a bounce-like effect
+            Vector2 reflectDirection = Vector2.Reflect(incomingDirection, hitNormal);
+            
+            // Blend between reflection and pure normal for more variety
+            // 70% normal (splash away from surface) + 30% reflection (maintain some momentum direction)
+            Vector2 baseDirection = (hitNormal * 0.7f + reflectDirection * 0.3f).normalized;
+            
+            // Spawn pieces in a cone around the base direction
+            for (int i = 0; i < pieceCount; i++)
+            {
+                // Calculate angle offset for this piece within the spread cone
+                float t = pieceCount > 1 ? i / (float)(pieceCount - 1) : 0.5f;
+                float angleOffset = Mathf.Lerp(-spreadAngle / 2f, spreadAngle / 2f, t);
+                float angleRadians = Mathf.Atan2(baseDirection.y, baseDirection.x) + angleOffset * Mathf.Deg2Rad;
+                
+                Vector2 pieceDirection = new Vector2(Mathf.Cos(angleRadians), Mathf.Sin(angleRadians));
+                
+                // Spawn trash piece slightly offset from impact point
+                Vector2 spawnOffset = pieceDirection * 0.2f; // Small offset to prevent clipping
+                GameObject piece = Instantiate(trashPiecePrefab, (Vector2)impactPoint + spawnOffset, Quaternion.identity);
+                
+                // Setup trash piece physics
+                Rigidbody2D pieceRb = piece.GetComponent<Rigidbody2D>();
+                if (pieceRb != null)
+                {
+                    // Apply force with some randomness for more natural spread
+                    float randomForce = pieceForce * Random.Range(0.8f, 1.2f);
+                    pieceRb.AddForce(pieceDirection * randomForce, ForceMode2D.Impulse);
+                    
+                    // Add some random spin
+                    pieceRb.AddTorque(Random.Range(-100f, 100f));
+                }
+                
+                Logging.Debug($"[TrashBagProjectile] Spawned trash piece {i} in direction {pieceDirection}");
+            }
+        }
+    }
+}
+