收口审计治理与套餐任务进展

Constraint: 在线热修前必须保存当前迭代分支全部有效代码进展
Confidence: medium
Scope-risk: broad
Directive: 后续修改需保持审计事件与业务事务边界一致
Tested: git diff --cached --check
Not-tested: 未运行全量测试，提交用于切换分支前保存既有工作

internal/application/approval/audit.go

@@ -0,0 +1,40 @@
+package approval
+
+import (
+	"context"
+
+	"gorm.io/gorm"
+)
+
+// AuditChange 描述通用审批链路一次实际状态变化。
+type AuditChange struct {
+	EventID            string
+	ActionCode         string
+	Summary            string
+	InstanceID         uint
+	BusinessType       string
+	BusinessID         uint
+	SubmitterAccountID uint
+	SubmitterSnapshot  []byte
+	Provider           string
+	BeforeExternalRef  string
+	AfterExternalRef   string
+	CorrelationID      string
+	ParentEventID      string
+	BeforeStatus       *int
+	AfterStatus        *int
+	ActorKind          string
+	ActorID            string
+	ActorName          string
+	Source             string
+	Result             string
+	ErrorSummary       string
+	Decision           string
+	IntegrationIDs     []string
+	OutboxEventID      string
+}
+
+// AuditWriter 在审批事实事务中追加统一 Audit Event。
+type AuditWriter interface {
+	WriteApproval(ctx context.Context, tx *gorm.DB, change AuditChange) error
+}