Bootstrap copied BFF and local accounts with public Sendico contracts (#34)

backend/contracts/sendico/api/parameters/recipients_ref.yaml

@@ -0,0 +1,9 @@
+components:
+  parameters:
+    RecipientsRef:
+      name: recipients_ref
+      in: path
+      required: true
+      description: Recipient reference, 24 hex chars.
+      schema:
+        $ref: ../../models/objectid.yaml#/components/schemas/ObjectId