Add CI validation helpers with explicit signature selection and owned results

include/Domito.MinCrypt.h

@@ -565,6 +565,13 @@ CiSetTrustedOriginClaimId(
 // See docs/ci-validate-file-object.md for evidence and version limitations.
 #define DOMITO_CI_VALIDATE_FLAG_BROADEN_ROOT_ACCEPTANCE 0x00000020UL
 
+// Descriptive experimental bit, not an official or isolated selector flag.
+// Participates in first-success guards in examined 22621/26100 x64 CI bodies;
+// also changes default-path policy and fallback. One 22631 TESTSIGNING-enabled
+// BthPS3 run confirms 0x20|0x80 returns its primary company signer. It is not an
+// arbitrary signer index, guaranteed primary selection, or a production default.
+#define DOMITO_CI_VALIDATE_FLAG_FIRST_SUCCESS_EXPERIMENTAL 0x00000080UL
+
 /**
 *  Given a file object, verify the signature and provide information regarding
 *   the certificates that was used for signing (the entire certificate chain)