A file-based well path whose source file is missing has a null wellPathGeometry(). Add null checks at the remaining call sites that dereferenced it without one, so operations on such a well path no longer crash:
- RimWellPathGroup: skip geometry merging for a child with no geometry (grouping runs on import and project load).
- RimWellPathFracture::computeFractureDirectionNormal: return undefined when geometry is missing.
- RivWellPathPartMgr: extend the existing well path null checks to also require geometry in the attribute, well measurement, and valve append paths.
- RimCompletionCellIntersectionCalc, RicExportLgrFeature, RicCreateMultipleWellPathLaterals, RigLasFileExporter, RiuWellPathComponentPlotItem: guard the geometry before use.
Sites that were already guarded or only reachable through guarded paths were left unchanged.