test(07-01): add failing tests for JWT lifecycle primitives

Co-authored-by: Cursor <cursoragent@cursor.com>

bouncer/context_test.go

@@ -1,6 +1,17 @@
 package bouncer
 
-import "testing"
+import (
+	"testing"
+	"time"
+)
+
+func TestPrincipalLocaleAndCutoff(t *testing.T) {
+	when := time.Unix(1_700_000_000, 0)
+	p := Principal{PreferredLocale: "pl", TokensValidAfter: when}
+	if p.PreferredLocale != "pl" || !p.TokensValidAfter.Equal(when) {
+		t.Fatalf("%+v", p)
+	}
+}
 
 func TestContextCredentialRoundTrip(t *testing.T) {
 	if _, ok := Credential(t.Context()); ok {