feat: T4 wave 6 - reminders and morning digest, next steps UI, warnings and notifications UI

- In-app reminders: task due (skips rescheduled tasks, catch-up wording)
  and a per-user morning digest step in the daily job
- Frontend: "Als Nächstes" on the colony page, "Heute" on the dashboard,
  inspection-due card, season chip, apiary overview fields, cleanup
  sheet for ended colonies
- Frontend: plausibility warnings that stay until dismissed, withdrawal
  spans in the calendar, notification bell with categories and links,
  notification settings in the profile
- ARCHITECTURE.md: T4a sections 11.1-11.10, assumptions 31-41, handler
  table and daily job step order

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

ApiCore-Frontend/src/lib/notification-settings/api.ts

@@ -0,0 +1,18 @@
+import { apiFetch } from "@/lib/auth/api-client";
+import type { NotificationSettings } from "./types";
+
+const PATH = "/profile/notification-settings";
+
+export function fetchNotificationSettings(): Promise<NotificationSettings> {
+  return apiFetch<NotificationSettings>(PATH);
+}
+
+/** Send only what changed; an omitted field stays as it is. */
+export function updateNotificationSettings(
+  patch: Partial<NotificationSettings>,
+): Promise<NotificationSettings> {
+  return apiFetch<NotificationSettings>(PATH, {
+    method: "PATCH",
+    body: JSON.stringify(patch),
+  });
+}

ApiCore-Frontend/src/lib/notification-settings/types.ts

@@ -0,0 +1,14 @@
+import type { NotificationCategory } from "@/lib/notifications/types";
+
+/** The signed-in user's own settings (GET/PATCH /profile/notification-settings). */
+export interface NotificationSettings {
+  taskDueEnabled: boolean;
+  digestEnabled: boolean;
+  /** HH:MM, 05:00 to 12:00 (Europe/Berlin). */
+  digestTime: string;
+  /** HH:MM or null; quiet hours are set or cleared only as a pair. */
+  quietFrom: string | null;
+  quietUntil: string | null;
+  telegramCategories: NotificationCategory[];
+  telegramDetail: boolean;
+}

ApiCore-Frontend/src/lib/notification-settings/validation.spec.ts

@@ -0,0 +1,62 @@
+import { describe, expect, it } from "vitest";
+import { settingsPatch, validateDigestTime, validateQuietHours } from "./validation";
+import type { NotificationSettings } from "./types";
+
+const base: NotificationSettings = {
+  taskDueEnabled: true,
+  digestEnabled: true,
+  digestTime: "06:30",
+  quietFrom: "21:00",
+  quietUntil: "06:30",
+  telegramCategories: ["TASK_DUE", "DIGEST"],
+  telegramDetail: true,
+};
+
+describe("validateDigestTime", () => {
+  it("rejects 04:30 with the German message", () => {
+    expect(validateDigestTime("04:30")).toBe(
+      "Bitte eine Uhrzeit zwischen 05:00 und 12:00 wählen.",
+    );
+  });
+
+  it("rejects 12:01, empty and malformed values", () => {
+    expect(validateDigestTime("12:01")).not.toBeNull();
+    expect(validateDigestTime("")).not.toBeNull();
+    expect(validateDigestTime("abc")).not.toBeNull();
+  });
+
+  it("accepts the bounds", () => {
+    expect(validateDigestTime("05:00")).toBeNull();
+    expect(validateDigestTime("12:00")).toBeNull();
+  });
+});
+
+describe("validateQuietHours", () => {
+  it("clears only as a pair", () => {
+    expect(validateQuietHours("", "")).toBeNull();
+    expect(validateQuietHours("21:00", "06:30")).toBeNull();
+    expect(validateQuietHours("21:00", "")).toBe(
+      "Bitte Beginn und Ende der Ruhezeit angeben oder beide leeren.",
+    );
+    expect(validateQuietHours("", "06:30")).not.toBeNull();
+  });
+});
+
+describe("settingsPatch", () => {
+  it("contains only changed fields", () => {
+    expect(settingsPatch(base, { ...base, digestTime: "07:00" })).toEqual({
+      digestTime: "07:00",
+    });
+  });
+
+  it("is empty when nothing changed", () => {
+    expect(settingsPatch(base, { ...base })).toEqual({});
+  });
+
+  it("sends null for both quiet fields when cleared", () => {
+    expect(settingsPatch(base, { ...base, quietFrom: null, quietUntil: null })).toEqual({
+      quietFrom: null,
+      quietUntil: null,
+    });
+  });
+});

ApiCore-Frontend/src/lib/notification-settings/validation.ts

@@ -0,0 +1,35 @@
+import type { NotificationSettings } from "./types";
+
+export const DIGEST_TIME_MIN = "05:00";
+export const DIGEST_TIME_MAX = "12:00";
+export const DIGEST_TIME_MESSAGE = "Bitte eine Uhrzeit zwischen 05:00 und 12:00 wählen.";
+export const QUIET_PAIR_MESSAGE = "Bitte Beginn und Ende der Ruhezeit angeben oder beide leeren.";
+
+const TIME_PATTERN = /^([01]\d|2[0-3]):[0-5]\d$/;
+
+/** HH:MM strings of one day compare correctly as text. */
+export function validateDigestTime(value: string): string | null {
+  if (!TIME_PATTERN.test(value) || value < DIGEST_TIME_MIN || value > DIGEST_TIME_MAX) {
+    return DIGEST_TIME_MESSAGE;
+  }
+  return null;
+}
+
+/** Quiet hours are both set or both empty. */
+export function validateQuietHours(from: string, until: string): string | null {
+  return Boolean(from) === Boolean(until) ? null : QUIET_PAIR_MESSAGE;
+}
+
+/** Only the fields that differ from what the server last sent. */
+export function settingsPatch(
+  original: NotificationSettings,
+  draft: NotificationSettings,
+): Partial<NotificationSettings> {
+  const patch: Partial<NotificationSettings> = {};
+  if (draft.taskDueEnabled !== original.taskDueEnabled) patch.taskDueEnabled = draft.taskDueEnabled;
+  if (draft.digestEnabled !== original.digestEnabled) patch.digestEnabled = draft.digestEnabled;
+  if (draft.digestTime !== original.digestTime) patch.digestTime = draft.digestTime;
+  if (draft.quietFrom !== original.quietFrom) patch.quietFrom = draft.quietFrom;
+  if (draft.quietUntil !== original.quietUntil) patch.quietUntil = draft.quietUntil;
+  return patch;
+}