fix: Add missing inflect dependency for g2p module

requirements.txt

@@ -30,6 +30,7 @@ pykakasi>=2.3.0  # Japanese text processing
 pyopenjtalk; python_version < "3.12"  # Japanese phonetics (Python 3.11 compatible)
 unidecode>=1.3.0  # Text normalization
 py3langid>=0.2.2  # Language detection
+inflect>=7.0.0  # English text normalization (required by g2p)
 
 # AI Model dependencies
 transformers==4.47.1  # Pinned for DiffRhythm2 compatibility