Changes made for Pathfinder V5 PC's.

JornsHyperDriveFlex now ships both the Twinmatic and Eco/TwinPro shape libraries inside a single configuration, and the user picks which one applies the first time the config is loaded. The choice persists in the install override; deleting that override is the way to switch variants on a given machine.

The data layer change was adding a VariantShapesCollection (variant ? thickness ? shapes) alongside the legacy ShapesCollection on MachineShapeLibrary, plus a new ShapeVariant field on ConfigurationStore that is set from a new ShapeVariantOverride entry during the override flatten. Routing is handled by the existing library["10mm"].SomeShape indexer, which now reads ActiveVariant — so none of the ~30 call sites needed changes. Critical detail in the flatten path: the variant is applied to the library before the per-thickness shape merge runs, so any shape override lands on the right variant.

The UI change reuses the existing RadioSelectionDialog. A new EnsureShapeVariantSelected method in ApplicationManager runs right after ValidateSelectedConfiguration during config load. It only fires when the library has variants and the override is unset, so legacy single-variant configs are unaffected and post-install loads skip the dialog. Four new strings were added to the Main FormResource.resx and its designer for the dialog.

The JSON migration spliced the existing JornsHyperDriveFlex shape tree (which was actually the EcoTwinPro shapes) under an EcoTwinPro variant key, and pulled the Twinmatic shapes from JornsTwinmaticClosedLoop in under a Twinmatic key. Everything outside the Shapes block in that file is byte-identical to the original, BOM preserved. No other configs were touched, and back-compat tests verify the legacy schema still round-trips.

Six new NUnit tests cover variant JSON round-trip, indexer routing, the fallback when ActiveVariant is unset, legacy back-compat, and the override flatten in both directions.