Added the catalogue models and seed to support phase 2 of the POC prototype in the Persistence package.

Packages/Persistence/Sources/Public/Models/User.swift

@@ -0,0 +1,27 @@
+import Foundation
+
+/// A `Sendable` snapshot of an account.
+public struct User: Sendable, Equatable {
+
+    // MARK: Properties
+
+    /// The account's identifier.
+    public let id: UUID
+    /// The account's normalized email address.
+    public let email: String
+    /// The name other people see.
+    public let displayName: String
+
+    // MARK: Initializers
+
+    public init(
+        id: UUID,
+        email: String,
+        displayName: String
+    ) {
+        self.id = id
+        self.email = email
+        self.displayName = displayName
+    }
+
+}