feat(backend): Webhooks mit HMAC-signierter Auslieferung (Modul 28)

WebhooksModule (WebhookSubscription: URL, Events, Secret, aktiv) mit
Event-Dispatcher, angehaengt an 10 Ereignisse in 8 bestehenden Services
(colony.created, inspection.created, queen.created, queen.replaced,
harvest.created, batch.created, batch.updated, product.stock_changed,
task.created, task.completed). Auslieferung ist best-effort und blockiert
die ausloesende Anfrage nicht bei Fehlern.

ApiCore-Backend/src/inspections/inspections.service.ts

@@ -1,12 +1,16 @@
 import { Injectable, NotFoundException } from '@nestjs/common';
 import { PrismaService } from '../prisma/prisma.service';
+import { WebhooksService } from '../webhooks/webhooks.service';
 import { Inspection, Task } from '../../generated/prisma';
 import { CreateInspectionDto } from './dto/create-inspection.dto';
 import { CreateTaskFromInspectionDto } from './dto/create-task-from-inspection.dto';
 
 @Injectable()
 export class InspectionsService {
-  constructor(private readonly prisma: PrismaService) {}
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly webhooks: WebhooksService,
+  ) {}
 
   async findAll(): Promise<Inspection[]> {
     return this.prisma.inspection.findMany({ orderBy: { date: 'desc' } });
@@ -33,9 +37,11 @@ export class InspectionsService {
     dto: CreateInspectionDto,
     actingUserId: string,
   ): Promise<Inspection> {
-    return this.prisma.inspection.create({
+    const inspection = await this.prisma.inspection.create({
       data: { ...dto, date: new Date(dto.date), userId: actingUserId },
     });
+    await this.webhooks.dispatch('inspection.created', inspection);
+    return inspection;
   }
 
   async createTaskFromInspection(