fix: localize document summaries and refine mobile coach

src/components/documents/__tests__/document-summary-block.test.tsx

@@ -55,11 +55,32 @@ describe("DocumentSummaryBlock — a stored summary", () => {
     expect(html).toContain("A discharge letter from a city hospital.");
     expect(html).toContain("14 Feb 2026");
     expect(html).toContain('data-slot="document-detail-summary"');
-    // Nothing claims it is being made — it already exists.
+    // A stored result stays visible and can be explicitly regenerated.
     expect(html).not.toContain("being prepared");
+    expect(html).toContain('data-slot="document-detail-summary-regenerate"');
+    expect(html).toContain("Generate again");
+    const header = html.match(
+      /<div[^>]*data-slot="document-detail-summary-header"[^>]*>/,
+    );
+    expect(header?.[0]).toMatch(/\bflex-col\b/);
+    expect(header?.[0]).toMatch(/\bsm:flex-row\b/);
     expect(html).not.toContain("document-detail-summary-generate");
   });
 
+  it("disables regeneration while a replacement is being generated", () => {
+    const html = base({
+      summary: "Stored prose.",
+      summaryState: "READY",
+      isGenerating: true,
+    });
+
+    const action = html.match(
+      /<button[^>]*data-slot="document-detail-summary-regenerate"[^>]*>/,
+    );
+    expect(action?.[0]).toMatch(/\sdisabled(=""|\s|>)/);
+    expect(html).toContain("Generating");
+  });
+
   it("shows a stored summary even if the state disagrees", () => {
     // The bytes are the truth. A stale state must never hide a real summary.
     const html = base({ summary: "Stored prose.", summaryState: "PENDING" });

src/components/documents/document-detail-sheet.tsx

@@ -260,6 +260,9 @@ export function DocumentDetailSheet({
   const autoRead = useDocumentsAutoAiRead(open && documentId !== null);
   const suggest = useSuggestDetails();
   const summary = useDocumentSummary();
+  // Stored generation has an independent mutation state so transient
+  // Summarise/Show text requests cannot change this block's spinner or result.
+  const storedSummary = useDocumentSummary();
   const indexDoc = useIndexDocument();
 
   const [mutationError, setMutationError] = useState<string | null>(null);
@@ -296,6 +299,7 @@ export function DocumentDetailSheet({
   useEffect(() => {
     suggest.reset();
     summary.reset();
+    storedSummary.reset();
     indexDoc.reset();
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [documentId]);
@@ -399,17 +403,29 @@ export function DocumentDetailSheet({
     summary.mutate({ mode: aiMode, target: aiTarget, output });
   };
 
-  // Generate the STORED summary from the detail block. Same endpoint as the
-  // action row, but the result is not routed into the transient panel: the
-  // route persists a screened-clean summary, so refetching the document shows
-  // it in place. This runs only on a click — nothing here generates on open.
+  // Generate or regenerate the STORED summary from the detail block. Only the
+  // stored-summary branch requests replacement; the empty-state action keeps
+  // first-write-wins if another worker or tab finishes while AI is running.
   const generateStoredSummary = () => {
     if (!aiTarget || !documentId) return;
-    summary.reset();
-    summary.mutate(
-      { mode: aiMode, target: aiTarget, output: "summary" },
+    storedSummary.reset();
+    storedSummary.mutate(
       {
-        onSuccess: () => {
+        mode: aiMode,
+        target: aiTarget,
+        output: "summary",
+        persist: true,
+        replace: doc?.summary != null,
+      },
+      {
+        onSuccess: (result) => {
+          if ("summary" in result) {
+            if (result.persistence === "withheld") {
+              toast.error(result.summary);
+            } else if (result.persistence === "failed") {
+              toast.error(t("documents.detail.saveError"));
+            }
+          }
           void queryClient.invalidateQueries({
             queryKey: queryKeys.inboundDocument(documentId),
           });
@@ -611,7 +627,7 @@ export function DocumentDetailSheet({
                   : null
               }
               aiEnabled={aiEnabled}
-              isGenerating={summary.isPending}
+              isGenerating={storedSummary.isPending}
               actionsDisabled={capability.isPending}
               onGenerate={generateStoredSummary}
             />

src/components/documents/document-summary-block.tsx

@@ -27,7 +27,7 @@
  * provider call. With no AI provider configured the block renders the state
  * without an action rather than an button that would 422.
  */
-import { FileText } from "lucide-react";
+import { FileText, RefreshCw } from "lucide-react";
 
 import { Button } from "@/components/ui/button";
 import { useTranslations } from "@/lib/i18n/context";
@@ -63,13 +63,42 @@ export function DocumentSummaryBlock({
 }) {
   const { t } = useTranslations();
 
-  // A stored summary wins over every state: it is shown from storage.
+  // A stored summary wins over every state: it is shown from storage. The
+  // adjacent action is explicit, so opening the sheet never spends a provider
+  // call; a successful replacement is persisted by the summary route.
   if (summary) {
     return (
-      <section className="space-y-1.5" data-slot="document-detail-summary">
-        <p className="text-sm leading-none font-medium">
-          {t("documents.detail.summary.title")}
-        </p>
+      <section className="space-y-2" data-slot="document-detail-summary">
+        <div
+          data-slot="document-detail-summary-header"
+          className="flex flex-col items-start gap-2 sm:flex-row sm:items-center sm:justify-between"
+        >
+          <p className="text-sm leading-none font-medium">
+            {t("documents.detail.summary.title")}
+          </p>
+          {aiEnabled ? (
+            <Button
+              type="button"
+              variant="ghost"
+              size="sm"
+              data-slot="document-detail-summary-regenerate"
+              onClick={onGenerate}
+              disabled={isGenerating || actionsDisabled}
+            >
+              <RefreshCw
+                className={
+                  isGenerating
+                    ? "size-4 animate-spin motion-reduce:animate-none"
+                    : "size-4"
+                }
+                aria-hidden
+              />
+              {isGenerating
+                ? t("documents.detail.summary.generating")
+                : t("documents.detail.summary.regenerate")}
+            </Button>
+          ) : null}
+        </div>
         <p className="text-foreground text-sm">{summary}</p>
         {generatedAtLabel ? (
           <p className="text-muted-foreground text-xs">{generatedAtLabel}</p>

src/components/documents/use-document-assist.ts

@@ -30,8 +30,13 @@ import {
   type DocumentAiTarget,
 } from "./document-ai-transport";
 
-/** The session-only describe result — a summary XOR the raw extracted text. */
-export type DocumentDescribeResult = { summary: string } | { text: string };
+/** The describe result: raw text, or a summary plus its storage outcome. */
+export type DocumentDescribeResult =
+  | {
+      summary: string;
+      persistence?: "stored" | "withheld" | "failed";
+    }
+  | { text: string };
 
 /**
  * The document-scoped AI capability probe (`/api/documents/inbound/capability`).
@@ -95,8 +100,8 @@ export function useSuggestDetails() {
 }
 
 /**
- * On-demand, session-only summary or extracted text. The result is rendered
- * once and never persisted (P2-D4); closing the panel discards it.
+ * On-demand summary or extracted text. Both stay transient unless the document
+ * summary block explicitly requests persistence or replacement.
  */
 export function useDocumentSummary() {
   return useMutation<
@@ -106,11 +111,13 @@ export function useDocumentSummary() {
       mode: DocumentAiMode;
       target: DocumentAiTarget;
       output: DocumentSummaryMode;
+      persist?: boolean;
+      replace?: boolean;
     }
   >({
-    mutationFn: ({ mode, target, output }) =>
+    mutationFn: ({ mode, target, output, persist = false, replace = false }) =>
       runDocumentAi<DocumentDescribeResult>({
-        path: `/api/documents/inbound/${target.documentId}/summary?mode=${output}`,
+        path: `/api/documents/inbound/${target.documentId}/summary?mode=${output}${persist ? "&persist=true" : ""}${replace ? "&replace=true" : ""}`,
         mode,
         target,
       }),