feat(frontend): Webhook-Verwaltung fuer Administratoren (Modul 28)

/settings/webhooks: Liste, Anlage-Dialog mit Ereignis-Auswahl und
einmaliger Secret-Anzeige (Kopieren), Loeschen. Sidebar-Eintrag unter
Verwaltung. Live in Chrome verifiziert (Anlegen/Kopieren/Loeschen,
SSRF-Ablehnung, Mobile-Breakpoint); dabei einen Reset-Bug im
Anlage-Dialog gefunden und behoben (Fertig-Button loeschte den
Dialogzustand nicht, da onOpenChange bei programmatischem Schliessen
nicht feuert).

ApiCore-Frontend/src/lib/webhooks/api.ts

@@ -0,0 +1,17 @@
+import { apiFetch } from "@/lib/auth/api-client";
+import { CreateWebhookInput, WebhookSubscription, WebhookSubscriptionWithSecret } from "./types";
+
+export function fetchWebhooks(): Promise<WebhookSubscription[]> {
+  return apiFetch<WebhookSubscription[]>("/webhooks");
+}
+
+export function createWebhook(input: CreateWebhookInput): Promise<WebhookSubscriptionWithSecret> {
+  return apiFetch<WebhookSubscriptionWithSecret>("/webhooks", {
+    method: "POST",
+    body: JSON.stringify(input),
+  });
+}
+
+export function deleteWebhook(id: string): Promise<void> {
+  return apiFetch<void>(`/webhooks/${id}`, { method: "DELETE" });
+}

ApiCore-Frontend/src/lib/webhooks/types.ts

@@ -0,0 +1,33 @@
+export const WEBHOOK_EVENTS = [
+  "colony.created",
+  "inspection.created",
+  "queen.created",
+  "queen.replaced",
+  "harvest.created",
+  "batch.created",
+  "batch.updated",
+  "product.stock_changed",
+  "task.created",
+  "task.completed",
+] as const;
+
+export type WebhookEvent = (typeof WEBHOOK_EVENTS)[number];
+
+export interface WebhookSubscription {
+  id: string;
+  url: string;
+  events: WebhookEvent[];
+  active: boolean;
+  createdByUserId: string | null;
+  createdAt: string;
+  updatedAt: string;
+}
+
+export interface WebhookSubscriptionWithSecret extends WebhookSubscription {
+  secret: string;
+}
+
+export interface CreateWebhookInput {
+  url: string;
+  events: WebhookEvent[];
+}