Adds a simple copy-to-clipboard button for users.
<input type="text" value="Copy this text" id="copyText">
<button onclick="copyText()">Copy</button>
<script>
function copyText() {
const copyInput = document.getElementById('copyText');
copyInput.select();
copyInput.setSelectionRange(0, 99999);
navigator.clipboard.writeText(copyInput.value);
alert('Copied successfully!');
}
</script>
