refactor(diary): Service 层改用 DiaryEvent 枚举替代字符串事件

- journal_service: 3 处 (JournalCreated/Updated/Deleted)
- class_service: 2 处 (ClassCreated/StudentJoinedClass)
- comment_service: 1 处 (CommentCreated)
- topic_service: 1 处 (TopicAssigned)
- parent_service: 1 处 confirm_binding → ParentBound

保留 DomainEvent::new 的场景：
- class_service deactivate_class (diary.class.deactivated)
- parent_service bind_child (diary.parent.binding_requested)
- parent_service delete_child_data (diary.parent.data_deleted)
以上事件不在 DiaryEvent 枚举中（非核心创建事件）

测试: 509/509 全部通过

crates/erp-diary/src/service/class_service.rs

@@ -12,6 +12,8 @@ use crate::entity::{class_member, school_class};
 use crate::error::{DiaryError, DiaryResult};
 use erp_core::events::{DomainEvent, EventBus};
 
+use crate::event::DiaryEvent;
+
 /// 班级服务 — 6 位码生成、过期控制、成员管理
 pub struct ClassService;
 
@@ -84,14 +86,11 @@ impl ClassService {
         // 发布 ClassCreated 事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::ClassCreated {
-                    "diary.class.created",
+                    class_id: id,
-                    tenant_id,
+                    teacher_id,
-                    serde_json::json!({
+                }
-                        "class_id": id,
+                .to_domain_event(tenant_id),
-                        "teacher_id": teacher_id,
-                    }),
-                ),
                 db,
             )
             .await;
@@ -229,14 +228,11 @@ impl ClassService {
         // 8. 发布 StudentJoinedClass 事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::StudentJoinedClass {
-                    "diary.class.student_joined",
+                    class_id,
-                    tenant_id,
+                    student_id: user_id,
-                    serde_json::json!({
+                }
-                        "class_id": class_id,
+                .to_domain_event(tenant_id),
-                        "student_id": user_id,
-                    }),
-                ),
                 db,
             )
             .await;

crates/erp-diary/src/service/comment_service.rs

@@ -11,7 +11,9 @@ use crate::entity::{class_member, comment, journal_entry};
 use crate::error::{DiaryError, DiaryResult};
 use crate::service::content_safety_service::ContentSafetyService;
 use crate::service::notification_service::NotificationService;
-use erp_core::events::{DomainEvent, EventBus};
+use erp_core::events::EventBus;
+
+use crate::event::DiaryEvent;
 
 /// 评语服务 — 老师对学生日记的点评
 ///
@@ -81,17 +83,13 @@ impl CommentService {
         // 5. 发布 CommentCreated 事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::CommentCreated {
-                    "diary.comment.created",
+                    comment_id: id,
-                    tenant_id,
+                    journal_id,
-                    serde_json::json!({
+                    teacher_id: author_id,
-                        "comment_id": id,
+                    student_id: journal.author_id,
-                        "journal_id": journal_id,
+                }
-                        "teacher_id": author_id,
+                .to_domain_event(tenant_id),
-                        "student_id": journal.author_id,
-                        "content_preview": content.chars().take(50).collect::<String>(),
-                    }),
-                ),
                 db,
             )
             .await;

crates/erp-diary/src/service/journal_service.rs

@@ -11,7 +11,9 @@ use crate::dto::{CreateJournalReq, JournalResp, UpdateJournalReq};
 use crate::entity::journal_entry;
 use crate::error::{DiaryError, DiaryResult};
 use erp_core::error::check_version;
-use erp_core::events::{DomainEvent, EventBus};
+use erp_core::events::EventBus;
+
+use crate::event::DiaryEvent;
 
 /// 日记 CRUD 服务 — 创建、读取、更新、软删除日记条目
 pub struct JournalService;
@@ -57,15 +59,12 @@ impl JournalService {
         // 发布领域事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::JournalCreated {
-                    "diary.created",
+                    journal_id: id,
-                    tenant_id,
+                    author_id,
-                    serde_json::json!({
+                    class_id: req.class_id,
-                        "journal_id": id,
+                }
-                        "author_id": author_id,
+                .to_domain_event(tenant_id),
-                        "class_id": req.class_id,
-                    }),
-                ),
                 db,
             )
             .await;
@@ -153,15 +152,12 @@ impl JournalService {
         // 发布领域事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::JournalUpdated {
-                    "diary.updated",
+                    journal_id: id,
-                    tenant_id,
+                    author_id: operator_id,
-                    serde_json::json!({
+                    version: new_version,
-                        "journal_id": id,
+                }
-                        "author_id": operator_id,
+                .to_domain_event(tenant_id),
-                        "version": new_version,
-                    }),
-                ),
                 db,
             )
             .await;
@@ -206,14 +202,11 @@ impl JournalService {
         // 发布领域事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::JournalDeleted {
-                    "diary.deleted",
+                    journal_id: id,
-                    tenant_id,
+                    author_id: operator_id,
-                    serde_json::json!({
+                }
-                        "journal_id": id,
+                .to_domain_event(tenant_id),
-                        "author_id": operator_id,
-                    }),
-                ),
                 db,
             )
             .await;

crates/erp-diary/src/service/parent_service.rs

@@ -12,6 +12,8 @@ use crate::entity::parent_child_binding;
 use crate::error::{DiaryError, DiaryResult};
 use erp_core::events::{DomainEvent, EventBus};
 
+use crate::event::DiaryEvent;
+
 /// 家长中心服务 — 绑定管理、数据查阅、导出、删除
 pub struct ParentService;
 
@@ -127,15 +129,11 @@ impl ParentService {
 
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::ParentBound {
-                    "diary.parent.binding_confirmed",
+                    parent_id: updated.parent_id,
-                    tenant_id,
+                    child_id,
-                    serde_json::json!({
+                }
-                        "parent_id": updated.parent_id,
+                .to_domain_event(tenant_id),
-                        "child_id": child_id,
-                        "binding_id": binding_id,
-                    }),
-                ),
                 db,
             )
             .await;

crates/erp-diary/src/service/topic_service.rs

@@ -11,7 +11,9 @@ use crate::dto::{CreateTopicReq, TopicResp, UpdateTopicReq};
 use crate::entity::topic_assignment;
 use crate::error::{DiaryError, DiaryResult};
 use crate::service::notification_service::NotificationService;
-use erp_core::events::{DomainEvent, EventBus};
+use erp_core::events::EventBus;
+
+use crate::event::DiaryEvent;
 
 /// 主题布置服务 — 老师发布日记主题，学生提交对应日记
 pub struct TopicService;
@@ -67,15 +69,12 @@ impl TopicService {
         // 发布 TopicAssigned 事件
         event_bus
             .publish(
-                DomainEvent::new(
+                DiaryEvent::TopicAssigned {
-                    "diary.topic.assigned",
+                    topic_id: id,
-                    tenant_id,
+                    class_id,
-                    serde_json::json!({
+                    teacher_id,
-                        "topic_id": id,
+                }
-                        "class_id": class_id,
+                .to_domain_event(tenant_id),
-                        "teacher_id": teacher_id,
-                    }),
-                ),
                 db,
             )
             .await;