Integrate typed port authoring and reviewable exchange workflows

crates/oa-core/src/validation.rs

@@ -2245,8 +2245,29 @@ pub fn can_parent(p: &Project, child_kind: Kind, layer: Layer, parent: Option<Id
         }),
     }
 }
-/// Uses the same relation rules as committed edits, without cloning a project.
+/// Sources for new interface roles; preserved legacy associations remain readable.
+pub fn can_create_interface_role(p: &Project, source: Id) -> bool {
+    p.elements.get(&source).is_some_and(|e| {
+        e.kind().is_performer()
+            || matches!(
+                crate::ports::port_contract(e),
+                Some(PortContract::Component { .. })
+            )
+    })
+}
+
+/// Feasibility of creating a relationship with the default authoring contract.
+/// An FE builder creates its typed ports; validating an exact unbound FE here
+/// would incorrectly hide every target. Exact records still require endpoints.
 pub fn can_connect(p: &Project, kind: RelationKind, source: Id, target: Id) -> bool {
+    if kind == RelationKind::FunctionalExchange {
+        return source != target
+            && [source, target].iter().all(|id| {
+                p.elements
+                    .get(id)
+                    .is_some_and(|e| e.layer() == Layer::Sa && e.kind() == Kind::Function)
+            });
+    }
     if kind == RelationKind::Allocation
         && p.relations
             .values()