1. calculateRowColBackProject: ERODE the coverage mask (blurred mask >=
   ROWCOL_BP_ERODE=0.95 ~ 16px inside at sigma 10) before the masked UM
   and averaging - the back-projection is unreliable near its own
   boundary and boundary garbage dominated the partially-covered EDGE
   columns in v013-ROWCOL-02 (per-x maxima ~1000 for x<14, interior
   clean at 13-39 counts). Excluded edge lines drop below MIN_COVER and
   take the legacy per-line fallback.

2. RT conditioning row/col (problem 2, borrowed from the oracle path,
   /jp4/ input unchanged):
   - REORDER: row/col now AFTER photometric+FPN. Measuring on raw
     captured the FPN's static line structure (rms ~6/12 counts) which
     the later FPN subtraction removed AGAIN - negative FPN line
     structure was injected into the output.
   - UM before averaging (new curt.rowcol_um_sigma, default 10, 0=off):
     profiles measured on an unsharp-masked copy, subtracted from the
     original - content no longer biases the averages and the max_abs
     gate acts on residual counts.
   - rowcol_max_abs default 50 (calibrated counts; configs saved before
     this change carry 0 = no gate - set 50 to enable).

3. CuasQC (Andrey's regression-protection design): per-product health
   statistics with sequence-independent pass bands, appended per run to
   <center>-QC.json; FAIL prints loudly, never aborts. Increment 1:
   ROWCOL vectors (rms<=25, scene-max p95<=500 - both of today's
   defects would have failed) + FPN (rms, row/col line-structure
   energy), hooked after calculation AND reuse in CorrectionFPN.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>