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/m1

@@ -0,0 +1,20 @@
+language variant
+name male1
+gender male 70
+
+pitch 75 109
+flutter 5
+roughness 4
+consonants 80 100
+
+formant 0  98 100 100
+formant 1  97 100 100
+formant 2  97  95 100
+formant 3  97  95 100
+formant 4  97  85 100
+formant 5 105  80 100
+formant 6  95  80 100
+formant 7 100 100 100
+formant 8 100 100 100
+
+//stressAdd -10 -10 -20 -20 0 0 40 70