// =============================================================================
// Copyright (c) 2025 - 2026 Haixing Hu.
//
// SPDX-License-Identifier: Apache-2.0
//
// Licensed under the Apache License, Version 2.0.
// =============================================================================
//! The canonical field-name candidate selected by policy classification.
/// Identifies the candidate that matched a configured field rule.
///
/// # Examples
///
/// ```
/// use qubit_redact::{FieldMatchKind, RedactionPolicy};
///
/// let policy = RedactionPolicy::builder()
/// .fields(|fields| {
/// fields.matching(qubit_redact::FieldNameMatching::ExactOrTokenSuffix);
/// fields.secret_sensitive("password");
/// })
/// .expect("the field rules should be valid")
/// .build()
/// .expect("the policy should be valid");
/// let classification = policy.classify_field("db_password");
/// assert_eq!(classification.match_kind(), Some(FieldMatchKind::TokenSuffix));
/// ```