Update documentation on shipping/freight costs

[metas-Kay]

• exisiting docs:
  • Wie richte ich Versand- und Frachtkosten ein?
  • How do I set up shipping and freight costs?
• update with additional info as discussed with metas-dh
• related to/originated from: https://github.com/metasfresh/me03/issues/15257#issuecomment-1564582953

Steps to be considered (and verified/tested and possibly added to the docs)

1. Create a product "Freight costs" with a price => in this stage, it can simply be added to a sales order manually as any other product too.
   • product category is not important (correct step in exisiting doc "Choose prod cat. Gebinde" => has no effect afais
2. For automation: Add entry in window/540000 (Versandkostenpauschale) with Lieferweg (Shipper), e.g. "Eigentransport"
3. Check window window/540660 (Freight Cost Shipper) and edit the breaks based on delivery value and add freight costs, if desired (or leave at zero)
   • Define country (in case of error in sales order that country cannot be found)
4. In bpartner customer
   • in customer line, choose "Delivery via Shipper"
   • in adv. edit menu, predefine freight cost entry (from before), shipper (Lieferweg)
5. When entering the sales order, make sure to set "Freight Cost Rule" Versandkostenpauschale (i.e. the entry recorded earlier)

Alternative: "Fixed Price" / "Festpreis" (if not using automation with above setup):

1. When entering a sales order, open adv. edit
2. Set "Versandkostenberechnung = Festpreis"
3. Scroll down to field "Versandkosten" and enter the desired costs
4. check how it is calculated and displayed on PDF etc.

Related issues

• https://github.com/metasfresh/me03/issues/3307 (see also https://github.com/metasfresh/metasfresh-documentation/issues/657)
• https://github.com/metasfresh/me03/issues/15257
• https://github.com/metasfresh/me03/issues/9861