Tests: a patch's continuity g3 is valid, g5 is the hostile word

patch_continuity_and_points_cap_a_tube listed "g3" among the values surface.patch must refuse,
from #1521 when a patch built G0 to G2. Since cb8712aa0 Construction::Patch builds G0 to G4
(continuity_order.rs: `Construction::Patch => (G0, G4)`), so g3 is accepted, as it must be;
the order above what a patch builds is g5.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/engine/src/cmd/surface.rs

@@ -1921,7 +1921,7 @@ mod tests {
         assert!(s.doc.to_json().contains("\"continuity\""), "the continuity is saved");
         // Hostile and misplaced values.
         for (key, v) in [
-            ("continuity", json!("g3")),
+            ("continuity", json!("g5")),
             ("continuity", json!("smooth")),
             ("continuity", json!(5)),
             ("continuity", json!([{"edge": "here", "g": "g1"}])),