[EdgeDB] Create PartnershipProducingMedium schema (#3072)

Co-authored-by: Carson Full <[email protected]>

Author: bryanjnelson

dbschema/migrations/00053.edgeql

@@ -0,0 +1,12 @@
+CREATE MIGRATION m1vp4elagp7wzixttjl3s6pk2q5ml2p4zq35vvdc3nouewe3qvcm3q
+    ONTO m1rqfvf4ah2ev4ncoxa6l7x5u6h6tssd6r7cbneshimgxzbtdzdppq
+{
+  CREATE TYPE Product::PartnershipProducingMedium EXTENDING Engagement::Child {
+      CREATE REQUIRED LINK partnership: default::Partnership {
+          ON TARGET DELETE DELETE SOURCE;
+          SET readonly := true;
+      };
+      CREATE REQUIRED PROPERTY medium: Product::Medium;
+      CREATE CONSTRAINT std::exclusive ON ((.engagement, .partnership, .medium));
+  };
+};

dbschema/partnership-producing-medium.esdl

@@ -0,0 +1,11 @@
+module Product {
+  type PartnershipProducingMedium extending Engagement::Child {
+    required partnership: default::Partnership {
+      readonly := true;
+      on target delete delete source;
+    };
+    required medium: Medium;
+    
+    constraint exclusive on ((.engagement, .partnership, .medium))
+  }
+}