* test: reproduce #268 (Panic from truck-topology lib.rs:186 when joining struts that end on a bore wall)
* Sew refuses edges whose ends weld to one vertex (#268)
The sewer welds vertices on a 1e-6 grid but only rejected edges shorter than
1e-9, so a sliver edge between the two welded its ends into one vertex and
truck-topology panicked ("Two same vertices cannot construct an edge") inside
the guard. Such an edge is now a degenerate-edge error before any truck call,
and the boolean takes its usual fallback.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: bherbruck <brennen.herbruck@gmail.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Persist typed sketch dimensions and bounded ordered configuration rules in format 8. Use exact occurrence paths and source identity for editing, movement, appearance, and mass. Preserve sheet material regions through cutting, folding, and exact DXF export; retain nested cavities and material islands.
Validation: cargo xtask ci passed, including 368 engine tests, 178 UI tests, 68 UI scenarios, 136 kernel tests, and the 10-crate wasm check. Actual preview workflows and legacy format-7 origin-corner reopening were inspected.