Handle broken DashboardWidgets correctly

• flag for broken widgets
• data check
• second template for broken widgets

created merge request !477 (merged) to address this issue

mentioned in merge request !477 (merged)

added part::backend part::frontend prio::2 type::bug labels

assigned to @nik and unassigned @ZugBahnHof

marked the checklist item flag for broken widgets as completed

marked the checklist item data check as completed

marked the checklist item second template for broken widgets as completed

changed title from Handle broken DahsboardWidgets correctly to Handle broken DashboardWidgets correctly

added 1 deleted label

assigned to @ZugBahnHof and unassigned @nik

closed with merge request !477 (merged)

mentioned in commit e546f60c