🎯 Phase 9.75D: Implement clone_box() vs share_box() responsibility separation for stateful Box types

Co-authored-by: moe-charm <217100418+moe-charm@users.noreply.github.com>

test_state_sharing_validation.nyash

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+// 🎯 Phase B-C 验证测试 - 确认状态共享修复是否有效
+static box Main {
+    init { array_test, map_test, buffer_test, socket_test }
+    main() {
+        // ArrayBox测试 
+        local arr
+        arr = new ArrayBox()
+        arr.push("hello")
+        me.array_test = arr.length()  // 期待: 1
+        
+        // MapBox测试
+        local map
+        map = new MapBox()
+        map.set("key1", "value1")
+        me.map_test = map.size()      // 期待: 1
+        
+        // BufferBox测试  
+        local buf
+        buf = new BufferBox()
+        buf.write([72, 101, 108, 108, 111])  // "Hello"
+        me.buffer_test = buf.length() // 期待: 5
+        
+        // SocketBox测试
+        local sock
+        sock = new SocketBox()
+        sock.bind("127.0.0.1", 8080)
+        me.socket_test = 1            // 暂时设为1，表示创建成功
+        
+        return me.array_test
+    }
+}