Introduced the `ResultFilePath` property in the `ZugferdInvoice` model to store the path of generated result PDFs. Added a new service, `PdfResultPackageService`, to create result PDFs by converting the original PDF to PDF/A-3b format and attaching a report file. Updated `Upload.cshtml` and `Upload.cshtml.cs` to handle and display the `ResultFilePath`.
Created a migration to add the `ResultFilePath` column to the database. Updated `Program.cs` to register the new service and added configuration sections in `appsettings.json` for input and output directories. Enhanced error handling and logging for better traceability.
Enhanced `ZugferdInvoice` model with default string values to prevent nulls. Updated `Upload.cshtml` to display parsed invoice data.
Refactored `Upload.cshtml.cs` to handle ZUGFeRD XML parsing and database storage. Introduced `ImportedInvoice` property and buffered file processing with `MemoryStream`.
Extended `ZugferdParserService` to support ZUGFeRD v1, v1.0 FeRD, and v2/Factur-X. Added version-specific parsing methods and namespaces. Improved date and decimal parsing for robustness.
Added database migration (`20260522084606_InitialCreate`) to define `ZugferdInvoices` table. Updated migration snapshot to reflect schema changes.
Fixed localization issue in `Upload.cshtml.cs` error message.
