feat: support time_zone for user registration context

authsession/internal/service/shared/shared_test.go

@@ -34,6 +34,19 @@ func TestParseClientPublicKey(t *testing.T) {
 	assert.Equal(t, ErrorCodeInvalidClientPublicKey, CodeOf(err))
 }
 
+func TestParseTimeZone(t *testing.T) {
+	t.Parallel()
+
+	timeZone, err := ParseTimeZone("  Europe/Kaliningrad  ")
+	require.NoError(t, err)
+	assert.Equal(t, "Europe/Kaliningrad", timeZone)
+
+	_, err = ParseTimeZone("Mars/Olympus")
+	require.Error(t, err)
+	assert.Equal(t, ErrorCodeInvalidRequest, CodeOf(err))
+	assert.Equal(t, "time_zone must be a valid IANA time zone name", err.Error())
+}
+
 func TestToSession(t *testing.T) {
 	t.Parallel()