feat: Adds basic tests for database client.

Sources/DatabaseClientLive/Employees.swift

@@ -9,7 +9,7 @@ public extension DatabaseClient.Employees {
     .init { create in
       let model = try create.toModel()
       try await model.save(on: database)
-      return model.toDTO()
+      return try model.toDTO()
     } delete: { id in
       guard let model = try await EmployeeModel.find(id, on: database) else {
         throw NotFoundError()
@@ -28,17 +28,17 @@ public extension DatabaseClient.Employees {
         break
       }
 
-      return try await query.all().map { $0.toDTO() }
+      return try await query.all().map { try $0.toDTO() }
 
     } get: { id in
-      try await EmployeeModel.find(id, on: database).map { $0.toDTO() }
+      try await EmployeeModel.find(id, on: database).map { try $0.toDTO() }
     } update: { id, updates in
       guard let model = try await EmployeeModel.find(id, on: database) else {
         throw NotFoundError()
       }
       try model.applyUpdate(updates)
       try await model.save(on: database)
-      return model.toDTO()
+      return try model.toDTO()
     }
   }
 }
@@ -150,14 +150,14 @@ final class EmployeeModel: Model, @unchecked Sendable {
     self.updatedAt = updatedAt
   }
 
-  func toDTO() -> Employee {
-    .init(
-      id: id,
+  func toDTO() throws -> Employee {
+    try .init(
+      id: requireID(),
       active: active,
-      createdAt: createdAt,
+      createdAt: createdAt!,
       firstName: firstName,
       lastName: lastName,
-      updatedAt: updatedAt
+      updatedAt: updatedAt!
     )
   }