feat: T4 wave 11 – bottling form with article values and confirmation, Telegram in the app

- Bottling form: jar size and best-before from the product with source,
  differs-hints before saving, prefill status, water-content confirmation
  naming the measured value, idempotency key renewed on body change;
  product form gets shelf life (months) and whole-gram jar weight.
- Telegram frontend: link card with step-up dialog, t.me-only deep link,
  status polling, unlink; system Telegram card with receiver/sender state
  and confirmed retry; StepUpDialog shared with the backup import.
- Reauth calls never refresh-and-retry on 401 (no double lockout count);
  German texts for expired session and 429; service worker never caches
  Telegram, notification settings and system responses.
- Telegram backend round 2: shared link removal on every disconnect path,
  lease released on shutdown, connection errors not counted as poison.
- ARCHITECTURE.md §2, §6 (Annahmen 56–58), §10, §11.12, §11.13; TASKS.md T4.

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

ApiCore-Backend/src/telegram/telegram-sender.ts

@@ -15,6 +15,7 @@ import { DRAIN_MAX_ROUNDS } from '../domain-events/domain-event-dispatcher';
 import { NotificationsService } from '../notifications/notifications.service';
 import { PrismaService } from '../prisma/prisma.service';
 import { lockRowForUpdate } from '../prisma/row-lock';
+import { removeLinkIn } from './telegram-link-removal';
 import { TelegramApiError } from './telegram-api-error';
 import { TelegramClient } from './telegram-client';
 import {
@@ -504,14 +505,9 @@ export class TelegramSender {
     }
     await this.prisma.$transaction(async (tx) => {
       await lockRowForUpdate(tx, 'NotificationPreference', userId);
-      const { count } = await tx.telegramLink.deleteMany({
-        where: { userId, chatId },
-      });
-      if (count === 1) {
-        await tx.notificationPreference.updateMany({
-          where: { userId },
-          data: { telegramEnabled: false },
-        });
+      // Link, switch and the waiting backlog end together (only if the link
+      // still points to this chat).
+      if (await removeLinkIn(tx, userId, 'chat unavailable', chatId)) {
         await this.notifications.record(
           {
             userId,