Add 22 Tax Withholding Category fixtures covering Thailand domestic
withholding (Taw.Paw. 4/2528, Sec. 50(2), Sec. 70) with rates and
thresholds. Fixtures ship without accounts; on import each Thai company
gets "Withholding Tax Payable" (Liability) and "Withholding Tax
Receivable" (Asset) created and the payable account linked. Company
on_update does the same for companies created later. Site-configured
accounts survive fixture re-import on migrate.
kurogeek