chore: add memo uid

web/src/components/MemoContent/HorizontalRule.tsx

+import { Divider } from "@mui/joy";
 import { BaseProps } from "./types";
 
 interface Props extends BaseProps {
@@ -5,7 +6,7 @@ interface Props extends BaseProps {
 }
 
 const HorizontalRule: React.FC<Props> = () => {
-  return <hr />;
+  return <Divider className="!my-3" />;
 };
 
 export default HorizontalRule;

web/src/components/MemoView.tsx

 import { Divider, Tooltip } from "@mui/joy";
+import copy from "copy-to-clipboard";
 import { memo, useEffect, useRef, useState } from "react";
 import { toast } from "react-hot-toast";
 import { useTranslation } from "react-i18next";
@@ -148,6 +149,11 @@ const MemoView: React.FC<Props> = (props: Props) => {
     });
   };
 
+  const handleCopyMemoId = () => {
+    copy(String(memo.id));
+    toast.success("Copied to clipboard!");
+  };
+
   const handleMemoContentClick = async (e: React.MouseEvent) => {
     const targetEl = e.target as HTMLElement;
 
@@ -245,6 +251,12 @@ const MemoView: React.FC<Props> = (props: Props) => {
                     <Icon.Trash className="w-4 h-auto mr-2" />
                     {t("common.delete")}
                   </span>
+                  <Divider className="!my-1" />
+                  <div className="w-full px-3 text-xs text-gray-400">
+                    <span className="cursor-pointer" onClick={handleCopyMemoId}>
+                      ID: <span className="font-mono">{memo.id}</span>
+                    </span>
+                  </div>
                 </div>
               </div>
             </>