Both IntegrationMultiSelectGrid and IntegrationSelectGrid had
duplicated logic for building widget-by-integration maps, category
labels, sorting, and filtering. Extract shared code into
integration-grid-shared.ts using objectEntries and IntegrationKind
typing. Use i18n keys for category badges and widget counts instead
of hardcoded strings. Remove useEffect for onSelectionChange in
multi-select grid — call it directly in the toggle callback.
Thomas Camlong
bfa2295a7c