feat: stabilize face attachments and closed spline workflows

docs/occurrence-workflows.md

@@ -51,3 +51,11 @@ Create Components from Bodies and Move Bodies to Component now add ownership-tra
 Transfers preserve the body's world pose through rotated or translated parents. Pending positions on the involved source and destination paths are captured atomically with the transfer so save/reopen retains that pose; unrelated pending positions remain pending. Undo and checkpoint restoration recover the original pending positions as well as the feature history; redo restores the captured transfer. The operation requires one source and one destination placement. Shared instance definitions with several placements are rejected because a single ownership change cannot preserve several different world poses. A component that supplies transfer history outside its subtree cannot be deleted until that dependent history is removed.
 
 Older files without transfer features keep their saved assignment and offset behavior. No transfer timestamp is inferred from their final ownership map. Paste New freezes externally authored geometry after its successful entry transfer and remaps internal transfers, then replays later modifiers once. All transfer commands validate and evaluate on a scratch document before adoption.
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+New face-attached sketches capture the selected body's producer, certified face and exact occurrence path, together with the sketch's authoring placement. A supported face follows source edits; a missing or incompatible source reports a lost attachment rather than choosing another nearby face. Opening Edit restores the saved authoring occurrence as view context without creating an undo entry. Older saved point-only face references retain their legacy behavior.
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+`sketch.create` accepts `plane:{face:[x,y,z],body:"world body name",index:faceIndex,path:[occurrenceIDs]}`. Coordinates and custom planes are world inputs. The optional path must match the selected body. Point-only face picks must resolve uniquely to a supported exact attachment. For an unsupported planar face, explicitly add `fixed:true` to keep its current plane; this creates no live boundary projection. Curved faces cannot become planar attachments through this option.
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+Use `sketch.redefine` with the sketch ID and a new plane to repair or convert an attachment. Its preview is disposable; Apply records one undo step. An optional `author_path` explicitly repairs a missing author placement. Rebinding a repeated owner from another active component requires that path. Changing the target or converting to a fixed plane detaches only the old automatic face borders, retaining their currently evaluated geometry and entity IDs; unrelated projection links remain live. Pending positions on the involved target and author paths are captured with the edit, while unrelated pending positions remain pending.
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+Paste New remaps internal certified targets and authoring paths to the copied definitions. Timeline paste reports retained external face targets and refuses translating such attachments until an explicit fixed-plane conversion establishes independent geometry. Rename preserves certified body identity; another producer using the same body name cannot repair a lost attachment.