8fa78423e6
- FfmpegFrameRateParser (pure): prefers avg_frame_rate= then r_frame_rate=, rational N/N/M, unknown/0 -> null. - IFrameRateProbe + FfmpegFrameRateProbe: derives sibling ffprobe.exe from the located ffmpeg dir, reuses the IDecodeProcess seam for the ffprobe subprocess text; null if ffprobe absent. - FfmpegLocator now also extracts ffprobe.exe (ProbeFileName) from the pinned archive, conditional so old caches without it degrade to no pacing. - Tests: 6 pure parser units + 1 probe integration via fake locator/process; FfmpegLocatorTests still green. 15/15, 0 warnings. Pacing (probe->delay) is slice 2b. Derivative reference: standard ffprobe avg_frame_rate probing used across OBS/media tooling.