feat: add candidate FreeCAD naming SDK and attachment oracles

Build and verify the candidate-only FreeCAD naming bridge and OCCT worker path, including three-stage StringHasher restoration. Add Datum, ShapeBinder, attachment-mode, and PartDesign structure oracles plus offline SDK build plans and CI boundary checks.

config/freecad-web-exact-parity-plan.json

@@ -56,7 +56,7 @@
         { "id": "EX-SK-02", "title": "Match Sketcher editing tools, autoconstraints, virtual space and UI lifecycle", "priority": "P0", "status": "in_progress", "dependencies": ["EX-SK-01", "EX-UI-03"], "deliverables": ["Pointer and keyboard editor oracle", "All editing tools", "Task and focus lifecycle"], "acceptance": ["Every tool supports success, failure, cancel, undo and redo with matching selection"], "evidence": ["check:freecad-sketcher-editor", "check:chrome-sketcher-bspline"], "exactBlockedBy": ["The full GUI tool and focus matrix is incomplete"] },
         { "id": "EX-PART-01", "title": "Complete all Part primitives, builders, booleans, healing and inspection", "priority": "P0", "status": "in_progress", "dependencies": ["EX-KER-01", "EX-TSN-04"], "deliverables": ["All Part commands and parameters", "Healing and tolerance tools", "Native history for local operations"], "acceptance": ["Success and failure outputs match native Shape, history and diagnostics"], "evidence": ["check:chrome-part-primitives", "check:freecad-golden-fixtures"], "exactBlockedBy": ["Current golden corpus does not enumerate every Part command and option"] },
         { "id": "EX-PD-01", "title": "Complete all PartDesign features, parameters and additive/subtractive combinations", "priority": "P0", "status": "in_progress", "dependencies": ["EX-PART-01", "EX-TSN-04"], "deliverables": ["Complete PartDesign feature matrix", "Body Tip and feature-list semantics", "Per-feature native history and naming"], "acceptance": ["Every feature edit, failure recovery and save-reopen matches FreeCAD"], "evidence": ["check:partdesign-closure", "check:freecad-sketcher-partdesign-abi", "check:chrome-partdesign-lifecycle"], "exactBlockedBy": ["The parameter contract covers the supported Facade subset, not every registered PartDesign TypeId or cross-product"] },
-        { "id": "EX-PD-02", "title": "Complete attachment, datum, ShapeBinder, SubShapeBinder and body workflows", "priority": "P0", "status": "pending", "dependencies": ["EX-PD-01", "EX-DOC-04"], "deliverables": ["All map modes and support rules", "Datum and binder lifecycle", "Multi-body and cross-document corpus"], "acceptance": ["Support migration, visibility, Tip and references remain exact through mutation"], "evidence": ["check:chrome-partdesign-lifecycle", "check:freecad-fcstd-roundtrip"], "exactBlockedBy": ["Complete datum/binder and multi-body oracle is absent"] }
+        { "id": "EX-PD-02", "title": "Complete attachment, datum, ShapeBinder, SubShapeBinder and body workflows", "priority": "P0", "status": "pending", "dependencies": ["EX-PD-01", "EX-DOC-04"], "deliverables": ["All map modes and support rules", "Datum and binder lifecycle", "Multi-body and cross-document corpus"], "acceptance": ["Support migration, visibility, Tip and references remain exact through mutation"], "evidence": ["check:chrome-partdesign-lifecycle", "check:freecad-fcstd-roundtrip", "check:freecad-partdesign-structure", "check:freecad-attachment-modes"], "exactBlockedBy": ["Native same-document, first cross-document SubShapeBinder cases, and the 55-mode registry/engine partition pass; executable geometry for every implemented mode/reference combination, other XLink modes, relink recovery and Web Chrome replay remain incomplete"] }
       ]
     },
     {