Guide sketch patterns with live previews and editable offsets (#966)

Sketch Mirror, rectangular and circular Pattern, and Offset now show a green live preview that follows the selection and settings; OK commits, Cancel leaves the sketch unchanged. The shared dialogs show the current selection step and source counts, sources can be toggled with Ctrl/Cmd-click, cleared and reselected.

Offsets keep editable driving distance dimensions (One Side, Two Sides, Symmetric) that update the derived curves without moving the source, with undo/redo and save/reopen. Format 19: older files keep their fixed offsets.

New dialog labels in en, zh, ja, de and ko.

Fixes #696. Fixes #517.

crates/ui-egui/tests/scenarios/sketch_mirror_dialog.json

@@ -0,0 +1,25 @@
+[
+ {"call":"ui.prefs","params":{"look_at_anim":false}},
+ {"call":"engine.execute","params":{"command":"sketch.create","params":{"plane":"XY"}}},
+ {"call":"engine.execute","params":{"command":"sketch.line","params":{"points":[[-30,10],[-15,10]]}}},
+ {"call":"engine.execute","params":{"command":"sketch.line","params":{"points":[[-15,10],[-15,25]]}}},
+ {"call":"engine.execute","params":{"command":"sketch.line","params":{"points":[[0,-10],[0,40]],"construction":true}}},
+ {"call":"ui.view","params":{"view":"top"}},
+ {"start":"sketch.mirror"},
+ {"expect":{"dialog":"SketchModify(Mirror)","tool":null}},
+ {"click":{"sketch":[-22.5,10]}},
+ {"click":{"sketch":[-15,17.5]}},
+ {"click":{"sketch":[-22.5,10]},"ctrl":true},
+ {"click":{"sketch":[-22.5,10]},"ctrl":true},
+ {"call":"ui.dialogInput","params":{"index":1}},
+ {"click":{"sketch":[0,20]}},
+ {"until":{"count":{"name":"sketch_preview_curves","value":2}}},
+ {"expect":{"sketch_curves":{"own":3}}},
+ {"click":{"handle":"dialog:clear:Mirror line"}},
+ {"click":{"sketch":[0,20]}},
+ {"until":{"count":{"name":"sketch_preview_curves","value":2}}},
+ {"click":{"handle":"dialog:OK"}},
+ {"expect":{"dialog":null,"sketch_curves":{"own":5},"errors":0}},
+ {"call":"engine.execute","params":{"command":"edit.undo","params":{}}},
+ {"expect":{"sketch_curves":{"own":3},"errors":0}}
+]