feat: add PKL schema for message formats

pkg/format/Macaroon.pkl.go

@@ -0,0 +1,16 @@
+// Code generated from Pkl module `format`. DO NOT EDIT.
+package format
+
+type Macaroon struct {
+	Location string `pkl:"location" json:"location,omitempty"`
+
+	Originator string `pkl:"originator" json:"originator,omitempty"`
+
+	Identifier string `pkl:"identifier" json:"identifier,omitempty"`
+
+	FirstParty []string `pkl:"first_party" json:"first_party,omitempty"`
+
+	ThirdParty []string `pkl:"third_party" json:"third_party,omitempty"`
+
+	Expiration int `pkl:"expiration" json:"expiration,omitempty"`
+}