Smarter approach to the cookies (#103)

* Smarter approach to the cookies

  - Single maxCookieSize = 1400 constant with clear documentation
  - Combined cookie storage for ~40-45% size reduction
  - Backward compatible migration from legacy cookies

* Tuneup the code.

main_simple_test.go

@@ -81,11 +81,11 @@ func TestIsTestMode_DefaultBehavior(t *testing.T) {
 // TestVerifyAudience tests the verifyAudience function
 func TestVerifyAudience(t *testing.T) {
 	tests := []struct {
-		name             string
 		tokenAudience    interface{}
+		name             string
 		expectedAudience string
-		expectError      bool
 		description      string
+		expectError      bool
 	}{
 		{
 			name:             "Audience matches",