feat: add email notifications for suffix approval process

Introduced email notifications for the suffix approval process:
- Notify prefix owners when a new suffix requires approval
- Notify users when their suffix has been approved

This helps keep stakeholders informed about the status of their suffix requests, improving transparency and workflow efficiency.

freedoi/resolver/views.py

@@ -10,6 +10,7 @@ from django.views.generic import (
 )
 from django.shortcuts import get_object_or_404, redirect
 from django.http import HttpResponseBadRequest, Http404
+from django.core.mail import send_mail
 from rest_framework import generics, permissions
 from rest_framework.exceptions import PermissionDenied
 from .serializers import SuffixSerializer, IdentifierSerializer
@@ -179,6 +180,13 @@ class SuffixCreateView(LoginRequiredMixin, CreateView):
             or form.instance.prefix.owner == self.request.user
         ):
             form.instance.approved = True
+        else:
+            send_mail(
+                "New Suffix Pending Approval",
+                f"A new suffix has been created by {self.request.user.email} and is pending approval.",
+                None,
+                [form.instance.prefix.owner.email],
+            )
 
         return super().form_valid(form)
 
@@ -216,6 +224,14 @@ class SuffixApprovalView(LoginRequiredMixin, UpdateView):
 
     def form_valid(self, form):
         form.instance.approved = True
+
+        send_mail(
+            "Suffix Approved",
+            f"Your suffix { form.instance.prefix.prefix }.{form.instance.suffix} has been approved.",
+            None,
+            [form.instance.owner.email],
+        )
+
         return super().form_valid(form)