Add full shell, replaceable Omics adapter and bilingual interaction

Implement approved specification #32 and tickets #33-#37. Keep host authentication server-verified and pin session interaction language. Compile scoped base selectors for browser compatibility and retain full gutters during CSS pruning.

frontend/src/viewers/PreviewGrid.tsx

@@ -1,5 +1,10 @@
 import { AgGridReact } from "ag-grid-react";
-import { AllCommunityModule, ModuleRegistry } from "ag-grid-community";
+import { useRef } from "react";
+import { AllCommunityModule, ModuleRegistry, type GridState } from "ag-grid-community";
+import { AG_GRID_LOCALE_EN, AG_GRID_LOCALE_IT } from "@ag-grid-community/locale";
+import { useI18n } from "../i18n";
+import "ag-grid-community/styles/ag-grid.css";
+import "ag-grid-community/styles/ag-theme-alpine.css";
 
 // Register AG Grid modules once at module load time
 ModuleRegistry.registerModules([AllCommunityModule]);
@@ -11,6 +16,9 @@ interface Props {
 
 /** Reusable read-only preview grid: columns + row tuples → AG Grid. */
 export function PreviewGrid({ columns, rows }: Props) {
+  const { locale } = useI18n();
+  const gridMessages: Readonly<Record<string, string>> = locale === "it" ? AG_GRID_LOCALE_IT : AG_GRID_LOCALE_EN;
+  const gridState = useRef<GridState>();
   const columnDefs = columns.map((col) => ({ field: col, headerName: col }));
 
   const rowData = rows.map((row) => {
@@ -23,8 +31,16 @@ export function PreviewGrid({ columns, rows }: Props) {
 
   return (
     <div className="overflow-hidden rounded-xl border border-border/70 shadow-xs">
-      <div className="ag-theme-alpine" style={{ height: 400, width: "100%" }}>
-        <AgGridReact columnDefs={columnDefs} rowData={rowData} />
+      <div className="ag-theme-alpine thot-preview-grid" style={{ height: 400, width: "100%" }}>
+        <AgGridReact
+          key={locale}
+          theme="legacy"
+          columnDefs={columnDefs}
+          rowData={rowData}
+          localeText={gridMessages}
+          initialState={gridState.current}
+          onStateUpdated={({ state }) => { gridState.current = state; }}
+        />
       </div>
     </div>
   );