NGS2 engine adapted from knack_pc e119d8af829024eeaa57d3780a5d95c1c8550981,
https://github.com/AbdelmoumenDeghbouche/knack_pc, including its PS4 structure adapter.
The engine originates in AnyPS5 (https://github.com/boykopovar/AnyPS5),
core/libs/prx/libSceNgs2.native, licensed GPL-2.0-only; its license is preserved here.
hevag_coefs.h retains its ISC notice. The remaining project sources retain their licenses.
A combined executable using this engine is distributed under GPL version 2.

Local changes: runtime logging/path adapter, direct float LibAtrac9 call,
name-based resolver and PS4 waveform/rack-info layout conversion; PS4 delay,
mastering matrix, limiter and blocking render synchronization.
