Add queued email notifications for collaboration events

apps/server/internal/email/test_helpers_test.go

@@ -0,0 +1,18 @@
+package email
+
+import (
+	"log/slog"
+	"testing"
+)
+
+func testLogger(t *testing.T) *slog.Logger {
+	t.Helper()
+	return slog.New(slog.NewTextHandler(&testWriter{t: t}, &slog.HandlerOptions{Level: slog.LevelWarn}))
+}
+
+type testWriter struct{ t *testing.T }
+
+func (w *testWriter) Write(p []byte) (int, error) {
+	w.t.Logf("%s", p)
+	return len(p), nil
+}