Terminal: measure characters with Unicode 11 widths, so an emoji takes the two columns the remote counts

src/DodoSSH.Client.Shell/WebAssets/terminal.html

@@ -52,6 +52,7 @@
   <script src="/vendor/xterm.js"></script>
   <script src="/vendor/addon-fit.js"></script>
   <script src="/vendor/addon-webgl.js"></script>
+  <script src="/vendor/addon-unicode11.js"></script>
   <script src="/terminal.js"></script>
 </body>
 </html>