reverse tool (easiest) and testCases then updated index file

src/pages/list/reverse/service.ts

@@ -0,0 +1,21 @@
+type SplitOperatorType = 'symbol' | 'regex';
+
+export function reverseList(
+    splitOperatorType: SplitOperatorType,
+    splitSeparator: string,
+    joinSeparator: string = '\n',
+    input: string,
+): string {
+    let array: string[] = [];
+    switch (splitOperatorType) {
+        case 'symbol':
+            array = input.split(splitSeparator);
+            break;
+        case 'regex':
+            array = input.split(new RegExp(splitSeparator)).filter(item => item !== '');
+            break;
+    }
+
+    const reversedList = array.reverse();
+    return reversedList.join(joinSeparator);
+}