feat: Wiederkehrende Aufgaben-Vorlagen (recurring task templates)

Neue TaskTemplate-Entität mit YEARLY/MONTHLY/INTERVAL_DAYS-Wiederholung.
Fällige Aufgaben werden lazy bei GET /tasks erzeugt (Compare-and-Swap auf
nextDueDate), damit mehrere API-Replicas im Kubernetes-Cluster dieselbe
Vorlage nicht doppelt feuern - ohne zusätzliche Cron-Abhängigkeit.

Frontend: Verwaltungsseite unter /settings/task-templates zum Anlegen,
Auflisten und Deaktivieren von Vorlagen.

ApiCore-Frontend/src/app/(app)/settings/task-templates/create-task-template-dialog.tsx

@@ -0,0 +1,206 @@
+"use client";
+
+import { FormEvent, useState } from "react";
+import { useMutation, useQueryClient } from "@tanstack/react-query";
+import { createTaskTemplate } from "@/lib/task-templates/api";
+import { TaskTemplateRecurrenceType } from "@/lib/task-templates/types";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { Label } from "@/components/ui/label";
+import { Textarea } from "@/components/ui/textarea";
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from "@/components/ui/select";
+import {
+  Dialog,
+  DialogContent,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
+
+const RECURRENCE_LABELS: Record<TaskTemplateRecurrenceType, string> = {
+  YEARLY: "Jährlich",
+  MONTHLY: "Monatlich",
+  INTERVAL_DAYS: "Alle X Tage",
+};
+
+const MONTH_LABELS = [
+  "Januar",
+  "Februar",
+  "März",
+  "April",
+  "Mai",
+  "Juni",
+  "Juli",
+  "August",
+  "September",
+  "Oktober",
+  "November",
+  "Dezember",
+];
+
+export function CreateTaskTemplateDialog() {
+  const queryClient = useQueryClient();
+  const [open, setOpen] = useState(false);
+  const [title, setTitle] = useState("");
+  const [description, setDescription] = useState("");
+  const [recurrenceType, setRecurrenceType] = useState<TaskTemplateRecurrenceType>("MONTHLY");
+  const [recurrenceMonth, setRecurrenceMonth] = useState("1");
+  const [recurrenceDayOfMonth, setRecurrenceDayOfMonth] = useState("1");
+  const [intervalDays, setIntervalDays] = useState("14");
+  const [error, setError] = useState<string | null>(null);
+
+  function reset() {
+    setTitle("");
+    setDescription("");
+    setRecurrenceType("MONTHLY");
+    setRecurrenceMonth("1");
+    setRecurrenceDayOfMonth("1");
+    setIntervalDays("14");
+    setError(null);
+  }
+
+  const mutation = useMutation({
+    mutationFn: createTaskTemplate,
+    onSuccess: () => {
+      void queryClient.invalidateQueries({ queryKey: ["task-templates"] });
+      setOpen(false);
+      reset();
+    },
+    onError: () => setError("Vorlage konnte nicht angelegt werden."),
+  });
+
+  function handleSubmit(event: FormEvent<HTMLFormElement>) {
+    event.preventDefault();
+    setError(null);
+    mutation.mutate({
+      title,
+      description: description || undefined,
+      recurrenceType,
+      recurrenceMonth: recurrenceType === "YEARLY" ? Number(recurrenceMonth) : undefined,
+      recurrenceDayOfMonth:
+        recurrenceType === "YEARLY" || recurrenceType === "MONTHLY"
+          ? Number(recurrenceDayOfMonth)
+          : undefined,
+      intervalDays: recurrenceType === "INTERVAL_DAYS" ? Number(intervalDays) : undefined,
+    });
+  }
+
+  return (
+    <Dialog
+      open={open}
+      onOpenChange={(next) => {
+        setOpen(next);
+        if (!next) reset();
+      }}
+    >
+      <Button onClick={() => setOpen(true)}>+ Neue Vorlage</Button>
+      <DialogContent>
+        <DialogHeader>
+          <DialogTitle>Neue wiederkehrende Aufgabe</DialogTitle>
+        </DialogHeader>
+        <form className="flex flex-col gap-4" onSubmit={handleSubmit}>
+          <div className="flex flex-col gap-2">
+            <Label htmlFor="template-title">Titel</Label>
+            <Input
+              id="template-title"
+              required
+              value={title}
+              onChange={(event) => setTitle(event.target.value)}
+            />
+          </div>
+          <div className="flex flex-col gap-2">
+            <Label htmlFor="template-description">Beschreibung</Label>
+            <Textarea
+              id="template-description"
+              value={description}
+              onChange={(event) => setDescription(event.target.value)}
+            />
+          </div>
+          <div className="flex flex-col gap-2">
+            <Label htmlFor="template-recurrence">Wiederholung</Label>
+            <Select
+              value={recurrenceType}
+              onValueChange={(value) =>
+                setRecurrenceType((value ?? recurrenceType) as TaskTemplateRecurrenceType)
+              }
+            >
+              <SelectTrigger id="template-recurrence" className="w-full">
+                <SelectValue>{RECURRENCE_LABELS[recurrenceType]}</SelectValue>
+              </SelectTrigger>
+              <SelectContent>
+                {(Object.keys(RECURRENCE_LABELS) as TaskTemplateRecurrenceType[]).map((option) => (
+                  <SelectItem key={option} value={option}>
+                    {RECURRENCE_LABELS[option]}
+                  </SelectItem>
+                ))}
+              </SelectContent>
+            </Select>
+          </div>
+          {recurrenceType === "YEARLY" ? (
+            <div className="flex flex-col gap-2">
+              <Label htmlFor="template-month">Monat</Label>
+              <Select
+                value={recurrenceMonth}
+                onValueChange={(value) => setRecurrenceMonth(value ?? recurrenceMonth)}
+              >
+                <SelectTrigger id="template-month" className="w-full">
+                  <SelectValue>{MONTH_LABELS[Number(recurrenceMonth) - 1]}</SelectValue>
+                </SelectTrigger>
+                <SelectContent>
+                  {MONTH_LABELS.map((label, index) => (
+                    <SelectItem key={label} value={String(index + 1)}>
+                      {label}
+                    </SelectItem>
+                  ))}
+                </SelectContent>
+              </Select>
+            </div>
+          ) : null}
+          {recurrenceType === "YEARLY" || recurrenceType === "MONTHLY" ? (
+            <div className="flex flex-col gap-2">
+              <Label htmlFor="template-day">Tag im Monat</Label>
+              <Input
+                id="template-day"
+                type="number"
+                min={1}
+                max={31}
+                required
+                value={recurrenceDayOfMonth}
+                onChange={(event) => setRecurrenceDayOfMonth(event.target.value)}
+              />
+            </div>
+          ) : null}
+          {recurrenceType === "INTERVAL_DAYS" ? (
+            <div className="flex flex-col gap-2">
+              <Label htmlFor="template-interval">Alle wie viele Tage</Label>
+              <Input
+                id="template-interval"
+                type="number"
+                min={1}
+                required
+                value={intervalDays}
+                onChange={(event) => setIntervalDays(event.target.value)}
+              />
+            </div>
+          ) : null}
+          {error ? (
+            <p role="alert" className="text-sm text-destructive">
+              {error}
+            </p>
+          ) : null}
+          <DialogFooter>
+            <Button type="submit" disabled={mutation.isPending}>
+              {mutation.isPending ? "Wird angelegt…" : "Anlegen"}
+            </Button>
+          </DialogFooter>
+        </form>
+      </DialogContent>
+    </Dialog>
+  );
+}

ApiCore-Frontend/src/app/(app)/settings/task-templates/page.tsx

@@ -0,0 +1,120 @@
+"use client";
+
+import { Repeat } from "lucide-react";
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import { toast } from "sonner";
+import { deactivateTaskTemplate, fetchTaskTemplates } from "@/lib/task-templates/api";
+import { TaskTemplate, TaskTemplateRecurrenceType } from "@/lib/task-templates/types";
+import { Badge } from "@/components/ui/badge";
+import { Button } from "@/components/ui/button";
+import { PageHeader } from "@/components/page-header";
+import {
+  Table,
+  TableBody,
+  TableCell,
+  TableHead,
+  TableHeader,
+  TableRow,
+} from "@/components/ui/table";
+import { CreateTaskTemplateDialog } from "./create-task-template-dialog";
+
+const RECURRENCE_LABELS: Record<TaskTemplateRecurrenceType, string> = {
+  YEARLY: "Jährlich",
+  MONTHLY: "Monatlich",
+  INTERVAL_DAYS: "Alle X Tage",
+};
+
+function describeRecurrence(template: TaskTemplate): string {
+  if (template.recurrenceType === "YEARLY") {
+    return `${RECURRENCE_LABELS.YEARLY} (Tag ${template.recurrenceDayOfMonth ?? "?"}.${template.recurrenceMonth ?? "?"}.)`;
+  }
+  if (template.recurrenceType === "MONTHLY") {
+    return `${RECURRENCE_LABELS.MONTHLY} (Tag ${template.recurrenceDayOfMonth ?? "?"})`;
+  }
+  return `Alle ${template.intervalDays ?? "?"} Tage`;
+}
+
+function formatDate(value: string): string {
+  return new Date(value).toLocaleDateString("de-DE");
+}
+
+export default function TaskTemplatesPage() {
+  const queryClient = useQueryClient();
+  const { data: templates, isLoading, isError } = useQuery({
+    queryKey: ["task-templates"],
+    queryFn: fetchTaskTemplates,
+  });
+
+  const deactivateMutation = useMutation({
+    mutationFn: deactivateTaskTemplate,
+    onSuccess: () => {
+      void queryClient.invalidateQueries({ queryKey: ["task-templates"] });
+      toast.success("Vorlage deaktiviert");
+    },
+    onError: () => toast.error("Vorlage konnte nicht deaktiviert werden"),
+  });
+
+  return (
+    <main className="flex flex-col gap-4 p-4 sm:p-6">
+      <PageHeader
+        icon={Repeat}
+        title="Wiederkehrende Aufgaben"
+        description="Vorlagen für regelmäßig automatisch angelegte Aufgaben verwalten"
+        gradient="var(--gradient-sky)"
+        actions={<CreateTaskTemplateDialog />}
+      />
+
+      {isLoading ? <p className="text-sm text-muted-foreground">Lädt…</p> : null}
+      {isError ? (
+        <p role="alert" className="text-sm text-destructive">
+          Vorlagen konnten nicht geladen werden.
+        </p>
+      ) : null}
+
+      {templates && templates.length === 0 ? (
+        <p className="text-sm text-muted-foreground">Noch keine Vorlagen angelegt.</p>
+      ) : null}
+
+      {templates && templates.length > 0 ? (
+        <div className="overflow-x-auto">
+          <Table>
+            <TableHeader>
+              <TableRow>
+                <TableHead>Titel</TableHead>
+                <TableHead>Wiederholung</TableHead>
+                <TableHead>Nächste Fälligkeit</TableHead>
+                <TableHead>Status</TableHead>
+                <TableHead className="text-right">Aktion</TableHead>
+              </TableRow>
+            </TableHeader>
+            <TableBody>
+              {templates.map((template) => (
+                <TableRow key={template.id}>
+                  <TableCell className="font-medium">{template.title}</TableCell>
+                  <TableCell>{describeRecurrence(template)}</TableCell>
+                  <TableCell>{formatDate(template.nextDueDate)}</TableCell>
+                  <TableCell>
+                    <Badge variant={template.active ? "default" : "outline"}>
+                      {template.active ? "Aktiv" : "Inaktiv"}
+                    </Badge>
+                  </TableCell>
+                  <TableCell className="text-right">
+                    <Button
+                      type="button"
+                      variant="ghost"
+                      size="sm"
+                      disabled={!template.active || deactivateMutation.isPending}
+                      onClick={() => deactivateMutation.mutate(template.id)}
+                    >
+                      Deaktivieren
+                    </Button>
+                  </TableCell>
+                </TableRow>
+              ))}
+            </TableBody>
+          </Table>
+        </div>
+      ) : null}
+    </main>
+  );
+}

ApiCore-Frontend/src/app/(app)/sidebar.tsx

@@ -16,6 +16,7 @@ import {
   type LucideIcon,
   MapPin,
   Package,
+  Repeat,
   Search,
   ShoppingBag,
   Upload,
@@ -85,6 +86,7 @@ const ADMIN_GROUP: NavGroup = {
     { label: "Audit-Log", href: "/settings/audit-log", icon: History },
     { label: "Webhooks", href: "/settings/webhooks", icon: Webhook },
     { label: "Automatisierungen", href: "/settings/automation-rules", icon: Zap },
+    { label: "Wiederkehrende Aufgaben", href: "/settings/task-templates", icon: Repeat },
     { label: "Import", href: "/settings/import", icon: Upload },
   ],
 };

ApiCore-Frontend/src/lib/task-templates/api.ts

@@ -0,0 +1,24 @@
+import { apiFetch } from "@/lib/auth/api-client";
+import { CreateTaskTemplateInput, TaskTemplate, UpdateTaskTemplateInput } from "./types";
+
+export function fetchTaskTemplates(): Promise<TaskTemplate[]> {
+  return apiFetch<TaskTemplate[]>("/task-templates");
+}
+
+export function createTaskTemplate(input: CreateTaskTemplateInput): Promise<TaskTemplate> {
+  return apiFetch<TaskTemplate>("/task-templates", {
+    method: "POST",
+    body: JSON.stringify(input),
+  });
+}
+
+export function updateTaskTemplate(id: string, input: UpdateTaskTemplateInput): Promise<TaskTemplate> {
+  return apiFetch<TaskTemplate>(`/task-templates/${id}`, {
+    method: "PATCH",
+    body: JSON.stringify(input),
+  });
+}
+
+export function deactivateTaskTemplate(id: string): Promise<TaskTemplate> {
+  return apiFetch<TaskTemplate>(`/task-templates/${id}/deactivate`, { method: "POST" });
+}

ApiCore-Frontend/src/lib/task-templates/types.ts

@@ -0,0 +1,43 @@
+import { TaskPriority } from "@/lib/tasks/types";
+
+export type TaskTemplateRecurrenceType = "YEARLY" | "MONTHLY" | "INTERVAL_DAYS";
+
+export interface TaskTemplate {
+  id: string;
+  title: string;
+  description: string | null;
+  priority: TaskPriority;
+  assignedUserId: string | null;
+  createdByUserId: string | null;
+  recurrenceType: TaskTemplateRecurrenceType;
+  recurrenceMonth: number | null;
+  recurrenceDayOfMonth: number | null;
+  intervalDays: number | null;
+  nextDueDate: string;
+  active: boolean;
+  createdAt: string;
+  updatedAt: string;
+}
+
+export interface CreateTaskTemplateInput {
+  title: string;
+  description?: string;
+  priority?: TaskPriority;
+  assignedUserId?: string;
+  recurrenceType: TaskTemplateRecurrenceType;
+  recurrenceMonth?: number;
+  recurrenceDayOfMonth?: number;
+  intervalDays?: number;
+}
+
+export interface UpdateTaskTemplateInput {
+  title?: string;
+  description?: string;
+  priority?: TaskPriority;
+  assignedUserId?: string;
+  recurrenceType?: TaskTemplateRecurrenceType;
+  recurrenceMonth?: number;
+  recurrenceDayOfMonth?: number;
+  intervalDays?: number;
+  active?: boolean;
+}