Add lead workflows, PDF signing, AR projects and photo gallery integration

GasTankAR/Data/Leads/LeadDetailRemoteService.swift

@@ -0,0 +1,29 @@
+import Foundation
+
+@MainActor
+protocol LeadDetailRemoteService {
+    func fetchDetail(id: String, salesCode: String) async throws -> LeadDetailDTO
+    func download(_ reference: LeadFileReference, leadID: String, salesCode: String) async throws -> Data
+}
+
+/// Transport boundary. A future HTTP adapter maps its response into this payload.
+struct LeadDetailDTO {
+    let detail: LeadDetail
+
+    func toDomain(expectedID: String) throws -> LeadDetail {
+        let documents = detail.offers.flatMap(\.documents)
+        let groups = detail.offers.flatMap(\.groups)
+        guard detail.lead.id == expectedID,
+              Set(detail.offers.map(\.id)).count == detail.offers.count,
+              Set(groups.map(\.id)).count == groups.count,
+              Set(documents.map(\.id)).count == documents.count,
+              Set(detail.photos.map(\.id)).count == detail.photos.count,
+              Set(detail.tankOptions.map(\.id)).count == detail.tankOptions.count,
+              detail.offers.allSatisfy({ !$0.id.isEmpty && !$0.title.isEmpty && $0.amount >= 0 }),
+              documents.allSatisfy({ !$0.id.isEmpty && !$0.title.isEmpty && $0.pageCount > 0
+                  && $0.file.kind == .pdf && !$0.file.id.isEmpty && !$0.file.version.isEmpty }),
+              detail.photos.allSatisfy({ $0.thumbnail.kind == .image && $0.original.kind == .image })
+        else { throw LeadError.invalidResponse }
+        return detail
+    }
+}