Parse #SKONTO#/#VERZUG# from Description in CII reader

[PeterSawatzki-MGGM]

Summary

• The CII writer already serializes payment terms as #SKONTO#TAGE=14#PROZENT=2.00# lines in the Description field for XRechnung profile
• The CII reader did not parse this format back — it only read structured XML elements (ApplicableTradePaymentDiscountTerms / ApplicableTradePaymentPenaltyTerms)
• This meant that XRechnung invoices from other systems using only the text-based format lost their discount/penalty information on read

Changes

• Added _tryReadXRechnungPaymentTerms() method to InvoiceDescriptor23CIIReader that:
  • Detects if any SpecifiedTradePaymentTerms/Description contains #SKONTO# or #VERZUG#
  • If found, parses each #SKONTO#TAGE=n#PROZENT=x.xx#BASISBETRAG=y.yy# line into a structured PaymentTerms object
  • Preserves freetext lines as the Description of the first payment term
  • Falls back to the existing structured XML reading if no #SKONTO#/#VERZUG# format is found
• Updated 4 roundtrip tests to expect structured PaymentTerms objects instead of raw description text

Context

Ported from the Delphi ZUGFeRD-for-Delphi library where this was implemented as TryReadXRechnungPaymentTerms.

Test plan

• All 295 existing tests pass
• Roundtrip tests verify write → read preserves PaymentTermsType, DueDays, Percentage, BaseAmount
• Freetext descriptions between #SKONTO# lines are preserved

[sonarqubecloud]

Quality Gate passed

Issues
5 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.6% Duplication on New Code

See analysis details on SonarQube Cloud