Phoneme types

The configuration enum recognizes the six current Piper phoneme type names:

Type	Phase 1 status
`text`	implemented in core
`espeak`	native and CLI backends implemented
`pinyin`	recognized configuration value, unavailable
`japanese`	recognized configuration value, unavailable
`thai`	recognized configuration value, unavailable
`hebrew`	recognized configuration value, unavailable
Arabic eSpeak voice	explicitly blocked until preprocessing is implemented

Selecting a deferred type without a custom backend raises an actionable UnsupportedPhonemeTypeError. Arabic eSpeak profiles raise UnsupportedCompatibilityError. Optional language dependencies are not imported by the core package.