fix(Handler): no internal instance cache

See merge request !123

For orders this is not needed. the internal instance cache causes more problems
due to the mix between uuid and id cache. the internal cache on uuid / id was therefore removed.
Orders have the data freshly fetched from the db anyway. therefore unnecessary.
In addition, a wrong order object was repeatedly retrieved when sending mail.

fix: consider if company field is required depend on b2b and b2c setting

See merge request !122

Related: quiqqer/order#163

fix(Order): copy all customer data to invoice

See merge request !120

fix: missing customer id

See merge request !118

Orders have not taken over the customer id.

Related: pcsg/buero#453

fix: mobile flex removed

See merge request !116

The UX was not optimal as a result. It was not clear that you could scroll and the guest order button was not visible.
For now flex removed and the login buttons are below each other

Next 2.x

See merge request !113

fix: only prevent writing of invoice_id in order if order already has a...

See merge request !112

Related: template-cologne#111

Add QUIQQER Tooling

See merge request !86

fix: only prevent writing of invoice_id in order if order already has a (non-temporary) invoice assigned

fix: status window use prefixed number

See merge request !108

fix: call to a member function getProducts() on null

See merge request !107

related: quiqqer/order-guestorder#8

feat(Basket): add product images

See merge request !106