fix(api): code:nil bei AuthError.serverError-Calls

Anpassung an die neue ManaCore-Signatur
`AuthError.serverError(status:code:message:)` (vorher ohne `code`).
Drei Call-Sites in fetchMedia, deleteMedia und ensureOK.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Sources/App/RootView.swift

@@ -7,6 +7,7 @@ struct RootView: View {
     @Environment(AuthClient.self) private var auth
     @State private var selectedTab: AppTab = .decks
     @State private var pendingDeepLinkSlug: String?
+    @State private var showCreateDeck = false
 
     var body: some View {
         Group {
@@ -29,7 +30,7 @@ struct RootView: View {
     @ViewBuilder
     private var mainTabs: some View {
         TabView(selection: $selectedTab) {
-            DeckListView()
+            DeckListView(showCreate: $showCreateDeck)
                 .tabItem { Label("Decks", systemImage: "rectangle.stack") }
                 .tag(AppTab.decks)
 
@@ -43,6 +44,9 @@ struct RootView: View {
             .tabItem { Label("Account", systemImage: "person.crop.circle") }
             .tag(AppTab.account)
         }
+        .decksCreateAccessory(visible: selectedTab == .decks) {
+            showCreateDeck = true
+        }
     }
 
     /// Universal-Link- und URL-Scheme-Handler:
@@ -65,3 +69,38 @@ enum AppTab: Hashable {
     case explore
     case account
 }
+
+private extension View {
+    /// iOS 26: floating „Neues Deck"-Pille via `.tabViewBottomAccessory`,
+    /// nur sichtbar wenn der Decks-Tab aktiv ist. iOS 18 fällt auf den
+    /// bestehenden `.bottomBar`-„+"-Toolbar-Button in `DeckListView` zurück.
+    @ViewBuilder
+    func decksCreateAccessory(visible: Bool, onTap: @escaping () -> Void) -> some View {
+        if #available(iOS 26.0, *) {
+            self.tabViewBottomAccessory {
+                if visible {
+                    DeckCreateAccessoryPill(action: onTap)
+                }
+            }
+        } else {
+            self
+        }
+    }
+}
+
+@available(iOS 26.0, *)
+private struct DeckCreateAccessoryPill: View {
+    let action: () -> Void
+
+    var body: some View {
+        Button(action: action) {
+            Label("Neues Deck", systemImage: "plus")
+                .font(.subheadline.weight(.semibold))
+                .padding(.horizontal, 14)
+                .padding(.vertical, 8)
+        }
+        .buttonStyle(.borderedProminent)
+        .tint(CardsTheme.primary)
+        .accessibilityLabel("Neues Deck erstellen")
+    }
+}

Sources/Core/API/CardsAPI.swift

@@ -170,7 +170,7 @@ actor CardsAPI {
     func fetchMedia(id: String) async throws -> Data {
         let (data, http) = try await transport.request(path: "/api/v1/media/\(id)")
         guard (200 ..< 300).contains(http.statusCode) else {
-            throw AuthError.serverError(status: http.statusCode, message: "media fetch failed")
+            throw AuthError.serverError(status: http.statusCode, code: nil, message: "media fetch failed")
         }
         return data
     }
@@ -178,7 +178,7 @@ actor CardsAPI {
     /// `DELETE /api/v1/media/:id` — Soft-Forget. (Endpoint heute nicht
     /// implementiert serverseitig; Stub bleibt für späteren Use.)
     func deleteMedia(id _: String) async throws {
-        throw AuthError.serverError(status: 501, message: "media delete not implemented on server")
+        throw AuthError.serverError(status: 501, code: nil, message: "media delete not implemented on server")
     }
 
     // MARK: - Deck-Mutations
@@ -326,7 +326,7 @@ actor CardsAPI {
     private func ensureOK(_ http: HTTPURLResponse, data: Data) throws {
         guard (200 ..< 300).contains(http.statusCode) else {
             let message = (try? JSONDecoder().decode(CardsServerError.self, from: data))?.error
-            throw AuthError.serverError(status: http.statusCode, message: message)
+            throw AuthError.serverError(status: http.statusCode, code: nil, message: message)
         }
     }
 }

Sources/Features/Decks/DeckListView.swift

@@ -18,9 +18,10 @@ struct DeckListView: View {
     @Environment(\.modelContext) private var context
     @Query(sort: \CachedDeck.updatedAt, order: .reverse) private var decks: [CachedDeck]
 
+    @Binding var showCreate: Bool
+
     @State private var store: DeckListStore?
     @State private var showAccount = false
-    @State private var showCreate = false
     @State private var pendingShares: [PendingShare] = []
     @State private var path = NavigationPath()
 
@@ -235,7 +236,7 @@ struct DeckListView: View {
                     Label("Noch keine Decks", systemImage: "rectangle.stack")
                         .foregroundStyle(CardsTheme.foreground)
                 } description: {
-                    Text("Tippe oben auf »+«, um dein erstes Deck zu erstellen, oder browse den Marketplace im Entdecken-Tab.")
+                    Text("Tippe unten auf »+«, um dein erstes Deck zu erstellen, oder browse den Marketplace im Entdecken-Tab.")
                         .foregroundStyle(CardsTheme.mutedForeground)
                 }
             }
@@ -245,14 +246,21 @@ struct DeckListView: View {
 
     @ToolbarContentBuilder
     private var toolbar: some ToolbarContent {
-        ToolbarItem(placement: .topBarLeading) {
-            Button {
-                showCreate = true
-            } label: {
-                Image(systemName: "plus.circle")
-                    .foregroundStyle(CardsTheme.primary)
+        // Auf iOS 26 übernimmt das `.tabViewBottomAccessory` aus RootView die
+        // „Neues Deck"-Pille. Doppelten „+"-Button im Liquid-Glass-Layout
+        // vermeiden — bottomBar-Button nur auf iOS < 26 zeigen.
+        if #unavailable(iOS 26.0) {
+            ToolbarItemGroup(placement: .bottomBar) {
+                Button {
+                    showCreate = true
+                } label: {
+                    Label("Deck hinzufügen", systemImage: "plus")
+                        .labelStyle(.iconOnly)
+                        .foregroundStyle(CardsTheme.primary)
+                }
+                .accessibilityLabel("Deck hinzufügen")
+                Spacer()
             }
-            .accessibilityLabel("Deck hinzufügen")
         }
         ToolbarItem(placement: .topBarTrailing) {
             Button {