Update VOUCHED list

https://github.com/anomalyco/opencode/issues/13204#issuecomment-3887062726

.github/VOUCHED.td

@@ -8,6 +8,7 @@
 #   - Denounce with minus prefix: -username or -platform:username.
 #   - Optional details after a space following the handle.
 adamdotdevin
+-florianleibert
 fwang
 iamdavidhill
 jayair