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/base/KnifeVariant.java

@@ -0,0 +1,61 @@
+package com.tiedup.remake.items.base;
+
+/**
+ * Enum defining all knife variants with their properties.
+ * Used by GenericKnife to create knife items via factory pattern.
+ *
+ * Each tier has its own cutting speed and durability:
+ * - Stone: slow, low capacity (emergency tool)
+ * - Iron: medium speed, reliable capacity
+ * - Golden: fast, high capacity (can cut through a padlock)
+ *
+ * Durability consumed per second = cuttingSpeed (1 durability = 1 resistance).
+ */
+public enum KnifeVariant {
+    STONE("stone_knife", 100, 5), // 100 dura, 5 res/s → 20s, 100 total resistance
+    IRON("iron_knife", 160, 8), // 160 dura, 8 res/s → 20s, 160 total resistance
+    GOLDEN("golden_knife", 300, 12); // 300 dura, 12 res/s → 25s, 300 total resistance
+
+    private final String registryName;
+    private final int durability;
+    private final int cuttingSpeed;
+
+    KnifeVariant(String registryName, int durability, int cuttingSpeed) {
+        this.registryName = registryName;
+        this.durability = durability;
+        this.cuttingSpeed = cuttingSpeed;
+    }
+
+    public String getRegistryName() {
+        return registryName;
+    }
+
+    /**
+     * Get the durability (max damage) of this knife.
+     * Total resistance a knife can cut = durability (1:1 ratio with cuttingSpeed drain).
+     *
+     * @return Durability value
+     */
+    public int getDurability() {
+        return durability;
+    }
+
+    /**
+     * Get the cutting speed (resistance removed per second).
+     * Also the durability consumed per second.
+     *
+     * @return Cutting speed in resistance/second
+     */
+    public int getCuttingSpeed() {
+        return cuttingSpeed;
+    }
+
+    /**
+     * Get max cutting time in seconds.
+     *
+     * @return Max cutting time (durability / cuttingSpeed)
+     */
+    public int getMaxCuttingTimeSeconds() {
+        return durability / cuttingSpeed;
+    }
+}