Merge current features with security hardening and automatic safe initialization

src/app/api/announcements/attachments/[id]/route.ts

@@ -5,6 +5,7 @@ import { NextResponse } from "next/server";
 
 import { getKitaSession } from "@/lib/auth-utils";
 import { prisma } from "@/lib/prisma";
+import { visibleAnnouncementAudiences } from "@/lib/announcement-access";
 
 export const runtime = "nodejs";
 
@@ -26,6 +27,7 @@ export async function GET(
       id,
       announcement: {
         kitaId: user.kitaId,
+        audience: { in: visibleAnnouncementAudiences(user) },
       },
     },
     select: {