UX improvements for the final step.

src/lib/google.ts

@@ -2,7 +2,10 @@ import { google } from 'googleapis';
 import { env } from '$env/dynamic/private';
 import quotedPrintable from 'quoted-printable';   //  tiny, zero-dep package
 
-export const scopes = ['https://www.googleapis.com/auth/gmail.send'];
+export const scopes = [
+	'https://www.googleapis.com/auth/gmail.send',
+	'https://www.googleapis.com/auth/userinfo.email'
+];
 
 export function getOAuthClient() {
 	return new google.auth.OAuth2(
@@ -61,11 +64,13 @@ export async function sendGmail(
   </body>
 </html>`;
 
-
 	const boundary = 'BOUNDARY';
 	const nl = '\r\n';                   // RFC-5322 line ending
 
-	const htmlQP = quotedPrintable.encode(message_html);
+	// Convert HTML to a Buffer, then to latin1 string for quotedPrintable.encode
+	const htmlBuffer = Buffer.from(message_html, 'utf8');
+	const htmlLatin1 = htmlBuffer.toString('latin1');
+	const htmlQP = quotedPrintable.encode(htmlLatin1);
 	const qrLines = qr_code.replace(/.{1,76}/g, '$&' + nl);
 
 	const rawParts = [