Make limiterEnabled control the stereo limiter stage only while leaving hard clipping active, and update UI/docs to distinguish saved RadioText from the active on-air value exposed at runtime.

Extend the RDS feature set with LPS and eRT support, add initial RDS2/logo-transfer wiring, update the control UI and refresh the PlutoSDR example configuration and reference docs.

Add the RDS 2 reference document used alongside the recent encoder and UI feature expansion.