ERPNext Invoice Consolidation Automation

I need a clean, repeatable workflow in ERPNext that will let me:

• Select multiple purchase invoices received from a single supplier
• Instantly generate one consolidated Sales Invoice addressed to my customer, carrying over every line-item from the source invoices
• Auto-populate that Sales Invoice with the supplier’s name, the original invoice numbers, each item’s full description, and the agreed payment terms
• Leave behind draft Purchase Invoices inside ERPNext for each of the originals so they remain traceable in Accounts Payable

The end result should feel native to the Sales Invoice module and respect the existing permission model. A short Python/Frappe script or a server-side custom app is fine as long as it works on the current ERPNext build and can be migrated easily.

Acceptance criteria
1. Running the function on a test company produces an exact one-to-one copy of every item from the selected supplier invoices inside a single Sales Invoice.
2. Supplier name, invoice numbers, detailed descriptions, and payment terms appear in clearly labelled fields or sections.
3. Draft Purchase Invoices are generated in the background without user intervention.
4. No core files are modified; solution survives future updates.

Provide the code, a quick setup guide, and a short demo video or screenshots so I can confirm it runs end-to-end.