Add email notification for staff

apps/submissions/emails.py

@@ -1,6 +1,6 @@
 """Outgoing email -- plan.md §7 (state-transition side effects).
 
-Five public functions, one per dedicated template:
+Six public functions, one per dedicated template:
 
   send_confirmation_email(submission)
       Guest path: token-link emailed immediately after `SubmitView` creates
@@ -32,7 +32,15 @@ Five public functions, one per dedicated template:
       when present (typically pickup instructions). Template:
       `emails/completed.*`.
 
-All five delegate to Django's email machinery. The backend is wired in
+  send_staff_verify_email(submission)
+      Operator broadcast fired on any transition into `status = verifying`.
+      One message to every active staff user with a non-empty email
+      (recipients placed in `bcc` so individual addresses stay hidden).
+      Surfaces the submitter's private `notes_for_op` -- not echoed on the
+      public detail page (plan.md §5) -- since the audience is staff only.
+      Template: `emails/staff_verify.*`.
+
+All six delegate to Django's email machinery. The backend is wired in
 `hamprint/settings/base.py`: Mailtrap via `django-anymail` when
 `MAILTRAP_API_TOKEN` is present, console when not. Send failures are caught
 + logged so a flaky transport never blocks the submission flow.
@@ -175,3 +183,62 @@ def send_completed_email(sub: Submission) -> bool:
     pickup-instruction the operator typed in admin reaches the user."""
     detail_url = f"{settings.SITE_URL}/p/{sub.slug}/"
     return _send("completed", sub, {"detail_url": detail_url})
+
+
+def send_staff_verify_email(sub: Submission) -> bool:
+    """Broadcast a "please verify" notice to every active staff user when
+    a submission lands in `verifying`. Fired by the centralised
+    `Submission.save()` hook so the worker's `processing -> verifying`
+    success branch AND any future admin path that returns a row to
+    `verifying` both trigger it (plan.md §7.3).
+
+    Recipients are placed in `bcc` so individual staff addresses stay
+    hidden from each other; `to` carries `DEFAULT_FROM_EMAIL` purely to
+    satisfy transports that reject envelopes with no `to`. Returns False
+    (without raising) when there is no active staff with a usable email
+    or when the transport surfaces an exception.
+    """
+    from django.contrib.auth import get_user_model
+
+    UserModel = get_user_model()
+    recipients = list(
+        UserModel.objects
+        .filter(is_staff=True, is_active=True)
+        .exclude(email="")
+        .values_list("email", flat=True)
+    )
+    if not recipients:
+        logger.info(
+            "no active staff with email; skipping staff_verify for %s", sub.slug
+        )
+        return False
+
+    admin_url = (
+        f"{settings.SITE_URL}/admin/submissions/submission/{sub.pk}/change/"
+    )
+    detail_url = f"{settings.SITE_URL}/p/{sub.slug}/"
+    context = {
+        "submission": sub,
+        "site_url": settings.SITE_URL,
+        "admin_url": admin_url,
+        "detail_url": detail_url,
+    }
+    subject, body_text, body_html = _render("staff_verify", context)
+
+    msg = EmailMultiAlternatives(
+        subject=subject,
+        body=body_text,
+        from_email=settings.DEFAULT_FROM_EMAIL,
+        to=[settings.DEFAULT_FROM_EMAIL],
+        bcc=recipients,
+    )
+    msg.attach_alternative(body_html, "text/html")
+    try:
+        msg.send()
+    except Exception:
+        logger.exception("failed to send staff_verify email for %s", sub.slug)
+        return False
+    logger.info(
+        "sent staff_verify email for %s to %d staff", sub.slug, len(recipients)
+    )
+    return True