chore: import upstream snapshot with attribution

lint/lintapi/violation.go

@@ -0,0 +1,33 @@
+// Copyright (c) 2026 Lark Technologies Pte. Ltd.
+// SPDX-License-Identifier: MIT
+
+// Package lintapi defines the shared types every lint domain returns from
+// its scan entry point. New lint domains (sibling packages under lint/)
+// MUST return []lintapi.Violation so cmd/main can aggregate and report
+// uniformly. The domain may add its own private types for internal use.
+package lintapi
+
+// Action enumerates the response modes for a violation.
+type Action string
+
+const (
+	// ActionReject hard-fails CI. Only REJECT contributes to a nonzero
+	// lintcheck exit code.
+	ActionReject Action = "REJECT"
+	// ActionLabel emits a diagnostic so CI can label the PR but does not fail.
+	ActionLabel Action = "LABEL"
+	// ActionWarning surfaces a reviewer-attention note without failing CI.
+	// CI does NOT exit nonzero on warnings; they are reviewer signal only.
+	ActionWarning Action = "WARNING"
+)
+
+// Violation describes a single lint hit. Rule identifies which check
+// produced it; the domain package owns the rule namespace.
+type Violation struct {
+	Rule       string
+	Action     Action
+	File       string
+	Line       int
+	Message    string
+	Suggestion string
+}