feat(fe): Add form field navigation - Enter key moves to next field

- Create useFormFieldNavigation composable for Tab-like Enter behavior
- KsTextField: Enter -> next field
- KsTextArea: Ctrl+Enter for newline, Enter -> next field
- KsSelect: Enter -> next field after selection
- Implements standard form navigation pattern across input components

frontend/src/shared/ui/components/index.ts

@@ -24,3 +24,5 @@ export { default as KsFormSection } from './KsFormSection.vue'
 export { default as KsFormSpan } from './KsFormSpan.vue'
 export { default as KsValidationSummary } from './KsValidationSummary.vue'
 export { default as KsSplitter } from './KsSplitter.vue'
+export { default as KArtsellMetricCard } from './KArtsellMetricCard.vue'
+