[FEAT]: Frontend live editable document section during field extraction

[marcvergees]

📝 Description

Create a new section in the frontend that displays the filled document as fields are extracted, allowing users to edit values before saving. This section should open as soon as the filling process starts. When an extracted field is available, it should be immediately rendered in the PDF, enabling the user to edit the field even while other fields are still being extracted. An animation should indicate each time a new field is rendered and written to the PDF.

💡 Rationale

Currently, users can't preview or edit the extracted data until the entire extraction is complete. Allowing real-time preview and input increases transparency, control, and user engagement, and improves trust in automated extraction.

🛠️ Proposed Solution

• Add a new frontend section that opens at the start of the extraction/filling process
• Render fields as soon as they're available, updating the PDF live
• Allow user editing of each field as soon as it's displayed
• Show an animation for each new field rendered or updated
• Ensure consistent sync with backend extraction events

✅ Acceptance Criteria

• Users can view and edit extracted fields before document save
• Live PDF preview updates with each extracted/edited field
• Animated indicator appears with each new field insertion
• Works seamlessly in Docker
• Documentation in docs/
• JSON output validates schema

📌 Additional Context

The feature will give users immediate insight and control during long-running or incremental document processing sessions, and keep them informed with smooth feedback via animation.