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[perNyfelt]

Summary

• Show staged attachments in the Attachments tab while a voucher is still an unsaved draft.
• Allow the GUI Add attachment action in draft mode and show MCP-provided attachment_path files immediately.
• Open draft attachments from their source path, mark them as not saved, and register them with the voucher when Save is pressed.
• Update MCP tool descriptions, localized feedback, and attachment/draft tests.

Why

AI-assisted voucher creation can now be reviewed with its receipt visible before the user saves the voucher. Discarding the draft does not create attachment records or copy files into the attachment archive.

Validation

• ./gradlew test --tests se.alipsa.accounting.service.AttachmentServiceTest --tests se.alipsa.accounting.ui.VoucherPanelNavigationTest
• ./gradlew codenarcMain
• ./gradlew build

No database schema changes.