refactor: remove Java code sections from all LeetCode Hot 100 markdown files

- Remove all "## Java 解法" sections and Java code blocks
- Replace "## Go 解法" with "## 解法"
- Remove "### Go 代码要点" and "### Java 代码要点" sections
- Keep all Go code sections intact
- Maintain complete documentation structure and content
- Update 22 markdown files in the LeetCode Hot 100 directory

16-LeetCode Hot 100/子集.md

@@ -116,56 +116,6 @@ func main() {
 
 ### Java 实现（回溯法）
 
-```java
-import java.util.ArrayList;
-import java.util.List;
-
-public class Subsets {
-
-    public List<List<Integer>> subsets(int[] nums) {
-        List<List<Integer>> result = new ArrayList<>();
-        List<Integer> current = new ArrayList<>();
-        backtrack(result, current, nums, 0);
-        return result;
-    }
-
-    private void backtrack(List<List<Integer>> result, List<Integer> current,
-                          int[] nums, int start) {
-        // 将当前子集加入结果
-        result.add(new ArrayList<>(current));
-
-        // 从 start 开始尝试包含每个元素
-        for (int i = start; i < nums.length; i++) {
-            // 选择当前元素
-            current.add(nums[i]);
-            // 递归处理下一个元素
-            backtrack(result, current, nums, i + 1);
-            // 撤销选择（回溯）
-            current.remove(current.size() - 1);
-        }
-    }
-
-    // 测试用例
-    public static void main(String[] args) {
-        Subsets solution = new Subsets();
-
-        // 测试用例1
-        int[] nums1 = {1, 2, 3};
-        System.out.println("输入: [1, 2, 3]");
-        System.out.println("输出: " + solution.subsets(nums1));
-
-        // 测试用例2
-        int[] nums2 = {0};
-        System.out.println("\n输入: [0]");
-        System.out.println("输出: " + solution.subsets(nums2));
-
-        // 测试用例3
-        int[] nums3 = {1, 2};
-        System.out.println("\n输入: [1, 2]");
-        System.out.println("输出: " + solution.subsets(nums3));
-    }
-}
-```
 
 ### Go 实现（迭代法-位掩码）
 
@@ -192,26 +142,6 @@ func subsetsBitMask(nums []int) [][]int {
 
 ### Java 实现（迭代法-位掩码）
 
-```java
-public List<List<Integer>> subsetsBitMask(int[] nums) {
-    int n = nums.length;
-    int total = 1 << n; // 2^n 个子集
-    List<List<Integer>> result = new ArrayList<>();
-
-    for (int mask = 0; mask < total; mask++) {
-        List<Integer> subset = new ArrayList<>();
-        for (int i = 0; i < n; i++) {
-            // 检查第 i 位是否为 1
-            if ((mask & (1 << i)) != 0) {
-                subset.add(nums[i]);
-            }
-        }
-        result.add(subset);
-    }
-
-    return result;
-}
-```
 
 ### Go 实现（级联法）