Email a set-password link on claim approval, flash identically either way

Two additions to the parent-claim flow: Club.contact_email (set from the
control panel, next to legal_name), and an email sent when an admin approves a
claim -- a real one-time set-password link built with allauth's own token
generator, so it lands in the same flow the login page's own reset would send
a parent to rather than a second, parallel one that could drift out of step
with it.

Never allowed to fail the approval: the family link and the guardian row are
real either way, and a mail server being briefly unreachable must not cost a
parent their place in the queue. The admin gets a distinct warning telling
them the email didn't go and to have the parent use "Forgot your password?"
instead.

The public submission flash keeps the enumeration guarantee the claim form
itself was built around: worded and timed identically whether or not a
matching child was found, sent before any lookup happens at all, mentioning
the club's contact email when the club has set one. A test compares the
rendered flash across a matching and a non-matching submission byte for byte.

One test-writing trap worth recording: assertRedirects follows the redirect
itself by default, and its own probe GET consumed the one-shot flash message
before a later explicit GET in the same test could see it --
fetch_redirect_response=False avoids the double-fetch.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

members/views.py

@@ -6,9 +6,11 @@ staff, and ClubStaffRequiredMixin would (rightly) turn them away.
 
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.http import Http404
-from django.shortcuts import render
+from django.shortcuts import redirect
+from django.utils.translation import gettext_lazy as _
 from django.views.generic import FormView, TemplateView
 
+from controlpanel.messages import notify
 from members.forms import ParentClaimForm
 from members.models import FamilyMembership, Member
 from members.services.claims import submit_claim
@@ -39,7 +41,17 @@ class ParentClaimView(ClubScopedPublicMixin, FormView):
 
     def form_valid(self, form):
         submit_claim(self.request.club, **form.cleaned_data)
-        return render(self.request, "members/parent_claim_submitted.html", {"club": self.request.club})
+
+        club = self.request.club
+        title = _("Request received")
+        body = _("%(club)s will check this against their records. If it matches, you'll get an email with a link to set your password.") % {"club": club.name}
+        if club.contact_email:
+            body += " " + _("Any questions, write to %(email)s.") % {"email": club.contact_email}
+        # Worded identically whether or not that child exists, and sent before any
+        # lookup happens at all -- a message that differed would tell an anonymous
+        # submitter which children the club has.
+        notify(self.request, f"s|{title}|{body}")
+        return redirect("members:parent_claim")
 
 
 class MyFamilyView(ClubScopedPublicMixin, LoginRequiredMixin, TemplateView):