Replaces naive ReplaceEntity approach with NX's proper
ReplaceFeatureBuilder API. This mirrors the interactive
right-click → Replace Feature workflow:
- SelectFeature: old sketch to replace
- ReplacementFeature: new sketch taking over
- DoAutomaticGeomMatch: auto-maps curves
- DeleteOriginalFeature: removes old after remap
- Fallback: manual delete if builder fails
All downstream features (extrude, trim) automatically
re-reference the new sketch.