fix(fe): ensure grid headers and container structure always stay rendered even when 0 records exist

frontend/src/shared/ui/DataGridShell.vue

@@ -18,7 +18,6 @@ const emit = defineEmits<{ pageChange: [value: { page: number; pageSize: number
 <template>
   <section class="ks-grid-shell-section" aria-label="데이터 표" :aria-busy="loading">
     <SkeletonLoader v-if="loading" type="table" :rows="6" />
-    <EmptyStatePlaceholder v-else-if="rows.length === 0" :message="emptyMessage" />
     <KsDataGrid v-else :rows="rows" :columns="columns" :height="props.height" />
     <KsPaginator
       v-if="props.page !== undefined && props.pageSize !== undefined && props.total !== undefined"

frontend/src/shared/ui/components/KsDataGrid.vue

@@ -61,7 +61,7 @@ function onGridReady(params: { api: { sizeColumnsToFit: () => void } }): void {
       :row-selection="rowSelectionOptions"
       :loading="props.loading"
       :auto-size-strategy="{ type: 'fitGridWidth' }"
-      :suppress-no-rows-overlay="props.rows.length > 0"
+      overlay-no-rows-template="<div class='ks-ag-empty-overlay'><span style='font-size:2rem;'>📭</span><p style='margin-top:8px;font-weight:600;color:var(--ks-color-neutral-700);'>조회된 데이터가 없습니다</p><p style='font-size:12px;color:var(--ks-color-neutral-500);'>검색 조건을 변경하거나 신규 데이터를 수집하세요.</p></div>"
       @grid-ready="onGridReady"
       @first-data-rendered="onGridReady"
       @sort-changed="onSortChanged"