OTBR Toolbox v3.1.0 — Phase 2: Consistency Phase 2 of the v3 modernization. Tested on Windows and Raspberry Pi, under both MATLAB and Octave. Highlights: - Consistent input validation across the Tier-1 API (validateattributes for invalid values; error for missing values; OTBR:UnknownArgument warning for unknown argument names — never a hard error mid-experiment). - Standardized v3.1 help/version headers with pointers to CHANGELOG.md. - Cross-platform fixes: platform-aware ESC key code and bIO KbCheck mapping (Windows vs Raspberry Pi); Octave fixes (time built-in shadowing, errorSave msgbox skip, Octave-on-Windows PTB paths, GStreamer trailing slash). - Latent-bug fixes (shuffleVectorRestricted swap-restart, touchBuffer nrFrames, fixationCross/showInstructions/closeWindow, ...). No breaking API changes; existing paradigm scripts run unchanged. See CHANGELOG.md [3.1.0] for the full per-function list.