refactor(meetings): change UserAppointmentStatsView from GET to POST

Modified UserAppointmentStatsView to accept POST requests instead of GET
and retrieve email from request body rather than from authenticated user.
This allows querying appointment statistics for any email address instead
of being limited to the current user's email.

Changes:
- Changed HTTP method from GET to POST
- Added email parameter extraction from request.data
- Updated filter to use provided email instead of request.user.email

meetings/views.py

@@ -176,9 +176,10 @@ class AppointmentStatsView(generics.GenericAPIView):
 class UserAppointmentStatsView(generics.GenericAPIView):
     permission_classes = [IsAuthenticated]
     
-    def get(self, request):
+    def post(self, request):
+        email = request.data.get('email')
         stats = AppointmentRequest.objects.filter(
-            email=request.user.email
+            email=email
         ).aggregate(
             total=Count('id'),
             pending=Count('id', filter=Q(status='pending_review')),