[FE][Certs] Copy cert code on click

frontend/src/certs/Registers/index.tsx

@@ -254,7 +254,17 @@ function RegisterEl(props: {register: Register, person: Person, onClick: () => v
                     </Show>
                     <Show when={!props.register.register_is_preview}>
                         <span class="font-mono">
-                            &nbsp;- {props.register.register_code}
+                            &nbsp;-&nbsp;
+                        </span>
+                        <span
+                            class="font-mono underline cursor-pointer hover:text-c-primary"
+                            onClick={() => {
+                                const code = props.register.register_code.toString();
+                                const paddedCode = code.padStart(4, "0");
+                                navigator.clipboard.writeText(paddedCode);
+                            }}
+                        >
+                            {props.register.register_code}
                         </span>
                     </Show>
                 </p>