fix(notdienst): resolve timezone offset mismatch in plan generation and fix linter warning in calendar modal

src/app/dashboard/notdienst/plan/actions.ts

@@ -47,8 +47,8 @@ export async function generatePlanAction(year?: number, month?: number) {
     where: {
       kitaId,
       date: {
-        gte: new Date(targetYear, targetMonth - 1, 1),
-        lt: new Date(targetYear, targetMonth, 1),
+        gte: new Date(Date.UTC(targetYear, targetMonth - 1, 1)),
+        lt: new Date(Date.UTC(targetYear, targetMonth, 1)),
       },
     },
     include: { child: { select: { familyId: true } } },
@@ -155,7 +155,8 @@ export async function updateAssignmentAction(
   const session = await requireRole([UserRole.ADMIN, UserRole.KOORDINATOR]);
   const kitaId = session.user.kitaId!;
 
-  const parsedDate = new Date(date);
+  const [yr, mo, dy] = date.slice(0, 10).split("-").map(Number);
+  const parsedDate = new Date(Date.UTC(yr, mo - 1, dy));
 
   try {
     await prisma.$transaction(async (tx) => {