feat(mail): one layout for all mails with logo, greeting, cards and footer

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

internal/api/notify_test.go

@@ -167,12 +167,18 @@ func TestDailySummary(t *testing.T) {
 	if len(*sent) != 1 {
 		t.Fatalf("expected one summary, got %d", len(*sent))
 	}
-	text := (*sent)[0].text
-	for _, want := range []string{"Überfällig", "Altlast", "Heute, 15:30 Uhr: Zahnarzt", "Morgen: Müll raus", "1 weitere"} {
+	// Grouped into sections, the same in text and HTML; the logo travels inside the mail
+	text, htmlBody := (*sent)[0].text, (*sent)[0].html
+	for _, want := range []string{"Guten Morgen", "ÜBERFÄLLIG\n• Altlast (seit ", "HEUTE\n• Zahnarzt (15:30 Uhr)", "MORGEN\n• Müll raus", "1 weitere"} {
 		if !strings.Contains(text, want) {
 			t.Fatalf("summary lacks %q:\n%s", want, text)
 		}
 	}
+	for _, want := range []string{"cid:" + mailLogoCID, ">Überfällig<", ">Zahnarzt<", "15:30 Uhr"} {
+		if !strings.Contains(htmlBody, want) {
+			t.Fatalf("summary HTML lacks %q", want)
+		}
+	}
 	srv.sendDailySummaries(now.Add(5 * time.Minute))
 	if len(*sent) != 1 {
 		t.Fatal("only one summary per day")
@@ -204,7 +210,7 @@ func TestDailySummaryIncludesGroupSharedLists(t *testing.T) {
 	set.DailySummary = domain.DailySummary{Enabled: true, Time: "07:00", Email: true}
 	_ = store.SetNotificationSettings(me.ID, set)
 	srv.sendDailySummaries(time.Date(2026, 10, 30, 7, 1, 0, 0, time.Local))
-	if len(*sent) != 1 || !strings.Contains((*sent)[0].text, "Bericht abgeben (Projekt)") {
+	if len(*sent) != 1 || !strings.Contains((*sent)[0].text, "Bericht abgeben (10:00 Uhr · Projekt)") {
 		t.Fatalf("group-shared task missing: %+v", *sent)
 	}
 }