Agregar campo username a User entity y DTO

- Columna username (unique, nullable) en auth.users
- Campo username en CreateUserDto y UpdateUserDto

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tts/piper/espeak-ng-data/voices/!v/pedro

@@ -0,0 +1,23 @@
+language variant
+
+name Pedro
+
+formant 0 100 150 100
+
+formant 1 95 100 80
+formant 2 95 100 80
+formant 3 100 100 90
+
+formant 4 100 100 100
+formant 5 100 100 100
+
+formant 6 100 100 100
+formant 7 100 100 100
+formant 8 100 100 100
+
+intonation 3
+
+pitch 82 118
+tone 600 255 1200 255 2000 255
+stressLength 0 1 2 3 4 5 6 7
+stressAdd 130 140 140 100 0 0 130 160