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/shell/WorkAreaPanel.tsx

@@ -12,6 +12,7 @@ import {
 } from "react";
 import { createPortal } from "react-dom";
 import { X } from "lucide-react";
+import { useI18n } from "../i18n";
 
 import { Button } from "../components/ui/button";
 
@@ -148,7 +149,7 @@ export const WorkAreaPanel = forwardRef<HTMLElement, WorkAreaPanelProps>(
       title,
       description,
       onClose,
-      closeLabel = "Close panel",
+      closeLabel,
       children,
       bodyClassName,
       footer,
@@ -160,6 +161,7 @@ export const WorkAreaPanel = forwardRef<HTMLElement, WorkAreaPanelProps>(
     },
     forwardedRef,
   ) {
+    const { t: translate } = useI18n();
     const panelHost = useContext(WorkAreaPanelHostContext);
     const titleId = useId();
     const descriptionId = useId();
@@ -236,8 +238,8 @@ export const WorkAreaPanel = forwardRef<HTMLElement, WorkAreaPanelProps>(
             data-drawer-close
             onClick={onClose}
             disabled={busy}
-            aria-label={closeLabel}
-            title={closeLabel}
+            aria-label={closeLabel ?? translate("Close panel")}
+            title={closeLabel ?? translate("Close panel")}
           >
             <X aria-hidden="true" />
           </Button>