notification-mail-recheck: Re-check DNS on Server › Settings

The owner, 2026-10-16: "Да, бери notification-mail-recheck". The records
of the server's own name can be checked again where they are shown: Re-
check DNS in Settings' page head (mockup 98e4dfc) posts to
POST /server/settings/dns-recheck (guard 52a9811), global role, which
runs Health's lookups - the server's address, then serverMail(true) - and
returns to /server/settings?rechecked=1, "DNS re-checked.". The
Notification mail box's end slot says when the records were checked
("The server's own name · checked 3 min ago", from the check's
CheckedAt; the old wording while nothing was looked up). A record that
has turned right comes back folded.

Tests: the page head's form and the end slot, and the Settings form
holding neither the re-check nor the right column
(TestSettingsRechecksTheMailRecords); the re-check skips the cache,
redirects and the page shows both records folded
(TestSettingsRecheckAsksForNotificationMailAgain); a domain
administrator gets 404 (globalOnlyRoutes). go vet + go test (26
packages) and make e2e on the test server for this tree.

Docs: architecture.md routes, the panel-redesign plan's route table,
guide § Settings, help (help.go word for word with the mockup's);
CHANGELOG [Unreleased]; roadmap row done. The roadmap's settings-save-row
note no longer claims the left-column form was needed for this - the
action went to the page head.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/web/handlers/handlers_notifications_test.go

@@ -176,7 +176,7 @@ func TestSettingsMailRecordsPublished(t *testing.T) {
 
 	out := getBody(t, h.HandleServerSettings, "/server/settings")
 	for _, want := range []string{
-		`id="notification-mail"`, `DNS records of the server's own name`,
+		`id="notification-mail"`, `The server's own name · checked just now`,
 		`<h3>DKIM</h3><span class="tag is-success is-light">published</span>`,
 		`selector <code>sp2026</code>`, `value="sp2026._domainkey.mail.example.org"`,
 		`<h3>SPF</h3><span class="tag is-success is-light">published</span>`,
@@ -313,3 +313,29 @@ func TestHealthRecheckAsksForNotificationMailAgain(t *testing.T) {
 		t.Errorf("after Re-check DNS both records should be published:\n%s", out)
 	}
 }
+
+// Re-check DNS on Settings asks for the same records again and returns to
+// Settings, where a record that has just been published comes back folded.
+func TestSettingsRecheckAsksForNotificationMailAgain(t *testing.T) {
+	h, zone, mail := serverMailStand(t)
+	if out := getBody(t, h.HandleServerSettings, "/server/settings"); strings.Count(out, `is-warning is-light">missing`) != 2 {
+		t.Fatalf("before publishing, both records should be missing:\n%s", out)
+	}
+
+	publishMail(zone, mail)
+	if out := getBody(t, h.HandleServerSettings, "/server/settings"); strings.Contains(out, `is-success is-light">published`) {
+		t.Fatal("the cached answer was not used: the test cannot tell a re-check from a fresh read")
+	}
+
+	rec := postFormAs(h.HandleSettingsDNSRecheck, globalPrincipal, "/server/settings/dns-recheck", nil, url.Values{})
+	if rec.Code != http.StatusSeeOther || rec.Header().Get("Location") != "/server/settings?rechecked=1" {
+		t.Fatalf("POST /server/settings/dns-recheck = %d to %q, want 303 to /server/settings?rechecked=1", rec.Code, rec.Header().Get("Location"))
+	}
+	out := getBody(t, h.HandleServerSettings, "/server/settings?rechecked=1")
+	if n := strings.Count(out, `<details class="sp-record">`); n != 2 {
+		t.Errorf("after Re-check DNS both records should be published and folded, %d are:\n%s", n, out)
+	}
+	if !strings.Contains(out, "DNS re-checked.") || !strings.Contains(out, "· checked just now") {
+		t.Errorf("Settings does not say the records were just re-checked:\n%s", out)
+	}
+}