Finding 1: Add TrimInPlace helper; apply trim→strip-[i]→empty-check order
in SetCalibrationEntry (matching Go Normalise()), so whitespace-padded
source/signal from WS clients normalise identically to config-file loads.
Finding 2: Trim unit before truncating to kMaxUnitLen, then walk back
continuation bytes (0x80-0xBF) to avoid leaving a partial UTF-8 rune,
matching Go's utf8.DecodeLastRuneInString loop.
Finding 3: BroadcastCalibration and HandleSaveSources now emit entries
sorted by source then signal (insertion sort over an index array, no STL),
producing byte-identical calibration frames and config files to the Go hub.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
