Commit 065118cf also deleted migrate_to_v11_6_5, which clamped
MaxSampleRate into LAME's supported [Hz_8000, Hz_48000] range on every
startup (the fix for #1116). Its replacement, ValidateEnumSettings, only
rejects values that fail to parse - but AAXClean.SampleRate defines
Hz_7350, Hz_64000, Hz_88200 and Hz_96000, so a hand-edited or
pre-v11.6.5 Settings.json could carry a valid-but-unsupported rate
straight into the encoder.
Clamp in the property getter and setter instead of a startup hook,
following the DailyDownloadLimitQuantity pattern.
Co-authored-by: rmcrackan <rmcrackan@gmail.com>