Markdown preview displays extracted fields in wrong order

[deanleigh]

When running an extraction, the Markdown preview panel displays extracted fields in an order that doesn't match any of the configured sources.

Expected:
The Markdown preview should reflect the same order as the source, mapping, or final generated page.

Actual:
Fields in the Markdown preview appear in a different order from:

• The Source tab (correct order)
• The Map tab (correct order)
• The generated Umbraco page (correct order)

Steps to reproduce:

1. Configure a workflow with multiple mapped fields across several blocks
2. Run an extraction on a source PDF
3. Open the Markdown preview

Environment:

• UpDoc version: 17.2.2
• Umbraco version: 17.3.4

Notes:
Only the preview is affected. The actual created Umbraco document has blocks in the correct order as defined in the blueprint. This appears to be a preview-layer rendering issue rather than a data problem.

Would be useful to know:

• What determines the preview's field order? (alias alphabetical, destination field array order, something else?)
• Is this configurable, or considered a bug?