Add JFJochViewerROIList to the side panel: a list of the dataset's ROIs
with selection, add (box/circle/azimuthal), rename and delete, plus a
statistics readout (sum/mean/std/max/valid/masked/centre-of-mass) for the
selected ROI, taken from the analysis output for the current image. Edits
emit a full ROIDefinition, routed to the worker's SetROIDefinition.
Per-ROI statistics now live in this panel rather than the canvas labels;
the diffraction image's labels show only the ROI name, and the ad-hoc
ROIIntegrationCPU computation there is removed in favour of the analysis
pipeline. The result widget now reports std dev instead of variance.
The single-ROI scratch panel remains for now and will be retired once the
interactive canvas editing replaces it.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>