Source fixture: synthetic invoice excerpt for extractx_eval tests.

This is one already-scoped document excerpt. It is used as an extraction
case only; customer identity and downstream account correlation remain outside
extractx.

VENDOR NAME: BrightPath Services
VENDOR ID: VND-1002

Invoice INV-1002 was issued on August 18, 2020 for maintenance services.
The subtotal amount is $250.00.
The applied tax rate is 4.25%.
The total amount due is $4.34.
Payment is due by September 17, 2020.
