[E-Document Core] - Skip duplicated E-Documents when receiving from service

[GMatuleviciute]

This pull request does not have a related issue as it's part of the delivery for development agreed directly with @altotovi @Groenbech96

Implementation

New functionality has been added to prevent duplicate E-Documents from being created during batch imports via service import. Improvements below have been implemented:

• The system checks for duplicates by using Vendor, External Document Number, and Document Date.
• If the document in the batch matches an existing document based on criteria above, duplicate E-Document will be automatically skipped during creation.

This update reduces unnecessary processing and ensures that only unique E-documents are created even with large batches.

Fixes #

[github-actions]

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