Make the Avalian Trader less robotic, add Avali Feather

Content/Rarities/AvalianItem.cs

@@ -0,0 +1,33 @@
+using Terraria.ModLoader;
+using Terraria;
+using Microsoft.Xna.Framework;
+using System;
+
+namespace ForgottenWawiTech.Content.Rarities
+{
+    public class AvalianItem : ModRarity
+    {
+        public override Color RarityColor
+        {
+            get
+            {
+                float time = Main.GlobalTimeWrappedHourly;
+
+                // Base color cycle: bright cyan <-> deep teal
+                const float cycleHz = 0.8f; // cycles per second
+                float t = (float)((Math.Sin(time * cycleHz * MathHelper.TwoPi) + 1f) * 0.5f); // 0..1
+
+                Color brightCyan = new Color(0, 255, 255);      // Bright cyan
+                Color deepTeal = new Color(0, 128, 160);        // Deep teal
+                Color baseColor = Color.Lerp(deepTeal, brightCyan, t);
+
+                // Add a subtle shimmer effect (faster, gentler than pulse)
+                const float shimmerHz = 2.0f;
+                float shimmer = (float)((Math.Sin(time * shimmerHz * MathHelper.TwoPi) + 1f) * 0.5f);
+                float brightness = 1f + 0.15f * shimmer; // subtle +15% max brightness variation
+
+                return baseColor * brightness;
+            }
+        }
+    }
+}