refactor: 重构lib代码（无实质性功能更新，可不更新）

lib/gacha/tool.js

@@ -0,0 +1,19 @@
+/**
+ * 欧非分析
+ * @param {number} ast
+ * @param {number[]} lst
+ */
+export const getLevelFromList = (ast, lst) => {
+  if (ast === 0) {
+    return 2;
+  }
+
+  let level = 0;
+  for (let numIndex = 0; numIndex < lst.length; numIndex++) {
+    if (ast <= lst[numIndex]) {
+      level = 4 - numIndex;
+      break;
+    }
+  }
+  return level;
+};