engine: interaction.tie, tie.edit and tie.delete

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

crates/engine/src/cmd/forms.rs

@@ -31,6 +31,7 @@ pub const BOUNDARY_CONDITION_DELETE: &[Field] = existing!("Boundary condition",
 pub const LOAD_DELETE: &[Field] = existing!("Load", C::Load);
 pub const FLUID_DOMAIN_DELETE: &[Field] = existing!("Fluid domain", C::FluidDomain);
 pub const CONTACT_DELETE: &[Field] = existing!("Contact", C::Contact);
+pub const TIE_DELETE: &[Field] = existing!("Tie", C::Tie);
 pub const STEP_DELETE: &[Field] = existing!("Step", C::Step);
 pub const SET_RESOLVE: &[Field] = existing!("Set", C::Set);
 
@@ -614,6 +615,18 @@ pub const CONTACT_EDIT: &[Field] = &[
     PENALTY,
     PENETRATION,
 ];
+pub const TIE: &[Field] = &[
+    NAME,
+    reference("main", "Main surface", C::Set).req(),
+    reference("secondary", "Secondary surface", C::Set).req(),
+    positive("position_tolerance", "Position tolerance", D::Length).hint("half the main element's thickness"),
+];
+pub const TIE_EDIT: &[Field] = &[
+    reference("name", "Tie", C::Tie).req(),
+    reference("main", "Main surface", C::Set).req(),
+    reference("secondary", "Secondary surface", C::Set).req(),
+    positive("position_tolerance", "Position tolerance", D::Length).hint("half the main element's thickness"),
+];
 pub const CONTACT_FIND: &[Field] = &[
     positive("tolerance", "Tolerance", D::Length).hint("a tenth of the mean face size"),
     flag("create", "Create pairs").def("false"),