Split Camino edge ordinals by endpoint

proto/camino/api.proto

@@ -129,7 +129,8 @@ message AddEdgeRequest {
   string source_field = 2;
   string to_object_id = 3;
   map<string, Value> fields = 4;
-  optional int32 ordinal = 5;
+  optional int32 source_ordinal = 5;
+  optional int32 target_ordinal = 6;
 }
 
 message AddEdgeResponse {
@@ -193,13 +194,14 @@ message CaminoEdge {
   string cardinality = 6;
   string inverse = 7;
   map<string, Value> fields = 8;
-  optional int32 ordinal = 9;
+  optional int32 from_ordinal = 9;
   string created_at = 10;
   string updated_at = 11;
   string from_projection = 12;
   string to_projection = 13;
   string from_cardinality = 14;
   string to_cardinality = 15;
+  optional int32 to_ordinal = 16;
 }
 
 message CaminoOp {