fix(web): admin — scan initial après création, retrait des fallbacks mock

La création d'une bibliothèque déclenche un scan initial avec état de
réessai en cas d'échec; suppression des fallbacks mock sur create/scan
pour ne masquer aucune erreur réelle.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/web/src/api/client.test.ts

@@ -31,6 +31,26 @@ describe("api fallback helpers", () => {
     expect(headers.has("Content-Type")).toBe(false);
   });
 
+  it("surfaces create library API errors without fallback", async () => {
+    const fetchMock = vi.fn().mockResolvedValue(
+      new Response(JSON.stringify({ message: "Library path does not exist" }), {
+        status: 400,
+        statusText: "Bad Request",
+        headers: { "Content-Type": "application/json" }
+      })
+    );
+    vi.stubGlobal("fetch", fetchMock);
+
+    await expect(api.createLibrary({ name: "Books", path: "/missing", enabled: true })).rejects.toThrow("Library path does not exist");
+  });
+
+  it("does not fallback when scan enqueue fails", async () => {
+    const fetchMock = vi.fn().mockRejectedValue(new Error("offline"));
+    vi.stubGlobal("fetch", fetchMock);
+
+    await expect(api.scanLibrary(42)).rejects.toThrow("offline");
+  });
+
   it("sends metadata source updates to the admin endpoint", async () => {
     const fetchMock = vi.fn().mockResolvedValue(
       new Response(JSON.stringify({ isbnPriorityEnabled: false, sources: [] }), {

apps/web/src/api/client.ts

@@ -185,15 +185,14 @@ export const api = {
   async createLibrary(input: CreateLibraryDto): Promise<LibraryDto> {
     return request<LibraryDto>("/admin/libraries", {
       method: "POST",
-      body: JSON.stringify(input),
-      fallback: { id: Date.now(), createdAt: new Date().toISOString(), updatedAt: new Date().toISOString(), ...input }
+      body: JSON.stringify(input)
     });
   },
   async deleteLibrary(id: number): Promise<void> {
     await request<{ ok: true }>(`/admin/libraries/${id}`, { method: "DELETE" });
   },
   async scanLibrary(id: number): Promise<JobDto> {
-    return request<JobDto>(`/admin/libraries/${id}/scan`, { method: "POST", fallback: mockJobs[0] });
+    return request<JobDto>(`/admin/libraries/${id}/scan`, { method: "POST" });
   },
   async jobs(): Promise<JobDto[]> {
     return request<JobDto[]>("/admin/jobs", { fallback: mockJobs });

apps/web/src/pages/AdminPage.tsx

@@ -13,6 +13,7 @@ export function AdminPage() {
   const [path, setPath] = useState("/library");
   const [error, setError] = useState<string>();
   const [success, setSuccess] = useState<string>();
+  const [scanRetryLibrary, setScanRetryLibrary] = useState<LibraryDto>();
 
   async function refresh() {
     setLoading(true);
@@ -53,28 +54,38 @@ export function AdminPage() {
     event.preventDefault();
     setError(undefined);
     setSuccess(undefined);
+    setScanRetryLibrary(undefined);
     try {
-      await api.createLibrary({ name, path, enabled: true });
+      const created = await api.createLibrary({ name, path, enabled: true });
       await refresh();
-      setSuccess(`Bibliothèque "${name}" ajoutée.`);
+      setName("Bibliotheque locale");
+      setPath("/library");
+      try {
+        await api.scanLibrary(created.id);
+        await refresh();
+        setSuccess(`Bibliothèque "${created.name}" ajoutée. Scan initial demandé.`);
+      } catch (scanError) {
+        setScanRetryLibrary(created);
+        setSuccess(
+          `Bibliothèque "${created.name}" ajoutée, mais le scan initial n'a pas pu être demandé. Tu peux réessayer le scan.`
+        );
+        setError(scanError instanceof Error ? `Scan initial impossible : ${scanError.message}` : "Scan initial impossible.");
+      }
     } catch (createError) {
-      const fallback = getApiFallback<LibraryDto>(createError);
-      if (fallback) setLibraries((current) => [fallback, ...current]);
-      setError(fallback ? "Creation en mode secours, synchronisation a retenter." : "Creation impossible");
+      setError(createError instanceof Error ? `Création impossible : ${createError.message}` : "Création impossible.");
     }
   }
 
   async function scan(id: number) {
     setError(undefined);
     setSuccess(undefined);
+    setScanRetryLibrary(undefined);
     try {
       await api.scanLibrary(id);
       await refresh();
       setSuccess("Scan demandé.");
     } catch (scanError) {
-      const fallback = getApiFallback<JobDto>(scanError);
-      if (fallback) setJobs((current) => [fallback, ...current]);
-      setError(fallback ? "Scan place en file de secours, statut a verifier." : "Scan impossible");
+      setError(scanError instanceof Error ? `Scan impossible : ${scanError.message}` : "Scan impossible.");
     }
   }
 
@@ -86,6 +97,7 @@ export function AdminPage() {
 
     setError(undefined);
     setSuccess(undefined);
+    setScanRetryLibrary(undefined);
     try {
       await api.deleteLibrary(library.id);
       setLibraries((current) => current.filter((item) => item.id !== library.id));
@@ -104,14 +116,22 @@ export function AdminPage() {
         </div>
         <ErrorRibbon message={error} />
         {success && <div className="success-ribbon">{success}</div>}
-        {error && (
+        {scanRetryLibrary ? (
+          <div className="retry-row">
+            <span>La bibliothèque est conservée dans la liste.</span>
+            <button className="ghost-button" onClick={() => scan(scanRetryLibrary.id)}>
+              <Play size={16} />
+              Réessayer le scan
+            </button>
+          </div>
+        ) : error ? (
           <div className="retry-row">
             <span>Les formulaires restent disponibles.</span>
             <button className="ghost-button" onClick={() => void refresh()}>
               Reessayer
             </button>
           </div>
-        )}
+        ) : null}
         <form className="admin-form" onSubmit={createLibrary}>
           <label>
             Nom de la bibliothèque