- Update FluidAudio to f47209a which includes ESpeakNG framework fix
- Fix VadConfig API compatibility: threshold -> defaultThreshold
- Add WorkspaceSettings to allow FluidAudio's unsafe build flags
This resolves the dyld crash: "Library not loaded: ESpeakNG.framework/Versions/A/ESpeakNG"
Fixed upstream in FluidInference/FluidAudio#159 and FluidInference/FluidAudio#160
Tested: All 4 UI tests pass
