Clean repo for open source release

Remove build artifacts, dev tool configs, unused dependencies,
and third-party source dumps. Add proper README, update .gitignore,
clean up Makefile.

src/main/java/com/tiedup/remake/items/ItemClassicCollar.java

@@ -0,0 +1,22 @@
+package com.tiedup.remake.items;
+
+import com.tiedup.remake.items.base.ItemCollar;
+import net.minecraft.world.item.Item;
+
+/**
+ * Classic Collar - Basic collar item
+ * Standard collar for marking ownership.
+ *
+ * Based on original ItemCollar from 1.12.2
+ * Phase 1: No ownership system yet, just a basic wearable collar
+ * Note: Collars have maxStackSize of 1 (unique items)
+ */
+public class ItemClassicCollar extends ItemCollar {
+
+    public ItemClassicCollar() {
+        super(
+            new Item.Properties()
+            // stacksTo(1) is set by ItemCollar base class
+        );
+    }
+}