feat: add audit logging and lesson statistics for clazz

- Add clazz_audit_log table with diesel migration for CRUD audit trail
- Add audit log backend: model, queries, handler, route
- Add audit log viewer in clazz detail modal (操作记录)
- Add student_lesson_stats API (GET /api/v1/clazz/stats/my-lessons)
- Add teacher_detail_stats API (GET /api/v1/clazz/stats/teacher-detail)
- Register all new routes in lib.rs

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

htykc/src/ws_clazz.rs

@@ -14,7 +14,7 @@ use htycommons::web::{
     HtySudoerTokenHeader,
 };
 use htykc_models::models::{
-    Clazz, ClazzRepeat, ReqClazz, ReqClazzRepeat, ReqClazzWithRepeat,
+    Clazz, ClazzAuditLog, ClazzRepeat, NewClazzAuditLog, ReqClazz, ReqClazzRepeat, ReqClazzWithRepeat,
 };
 use std::collections::HashMap;
 use std::ops::DerefMut;
@@ -27,6 +27,37 @@ fn current_org_id_from_auth(token: &AuthorizationHeader) -> Option<String> {
         .and_then(|decoded| decoded.current_org_id)
 }
 
+fn hty_id_from_auth(token: &AuthorizationHeader) -> Option<String> {
+    jwt_decode_token(&(*token).clone())
+        .ok()
+        .and_then(|decoded| decoded.hty_id)
+}
+
+fn write_clazz_audit_log(
+    db_pool: &Arc<DbState>,
+    clazz_id: &str,
+    action: &str,
+    operator_hty_id: &str,
+    changes: Option<serde_json::Value>,
+    org_id: Option<String>,
+) {
+    if let Ok(conn) = fetch_db_conn(db_pool) {
+        let _ = ClazzAuditLog::insert(
+            &NewClazzAuditLog {
+                id: uuid(),
+                clazz_id: clazz_id.to_string(),
+                action: action.to_string(),
+                operator_hty_id: operator_hty_id.to_string(),
+                operator_name: None,
+                changes,
+                created_at: current_local_datetime(),
+                org_id,
+            },
+            extract_conn(conn).deref_mut(),
+        );
+    }
+}
+
 pub async fn find_all_non_repeatable_within_date_range(
     sudoer: HtySudoerTokenHeader,
     host: HtyHostHeader,
@@ -666,6 +697,23 @@ async fn raw_update_clazz(
         extract_conn(fetch_db_conn(&db_pool)?).deref_mut(),
     )?;
 
+    // Audit log
+    let operator_id = hty_id_from_auth(&token).unwrap_or_default();
+    let action = if in_kecheng.is_delete == Some(true) { "DELETE" } else { "UPDATE" };
+    write_clazz_audit_log(
+        &db_pool,
+        &id_kecheng,
+        action,
+        &operator_id,
+        Some(serde_json::json!({
+            "is_delete": in_kecheng.is_delete,
+            "clazz_name": in_kecheng.clazz_name,
+            "start_from": in_kecheng.start_from,
+            "end_by": in_kecheng.end_by,
+        })),
+        current_org_id,
+    );
+
     Ok(())
 }
 
@@ -848,11 +896,24 @@ async fn raw_create_clazz_with_repeat(
         (to_create_kecheng, to_create_kecheng_repeat),
     );
 
-    let out_result = raw_create_clazz_with_repeat_tx(params, db_pool);
+    let out_result = raw_create_clazz_with_repeat_tx(params, db_pool.clone());
 
     match out_result {
         Ok(out) => {
             debug!("created_kecheng: {:?}", out);
+            write_clazz_audit_log(
+                &db_pool,
+                &new_clazz_id,
+                "CREATE",
+                &id_user,
+                Some(serde_json::json!({
+                    "clazz_name": in_kecheng.clazz_name,
+                    "start_from": in_kecheng.start_from,
+                    "end_by": in_kecheng.end_by,
+                    "is_repeat": in_kecheng.is_repeat,
+                })),
+                current_org_id.clone(),
+            );
             Ok(out)
         }
         Err(e) => Err(anyhow!(HtyErr {
@@ -862,6 +923,30 @@ async fn raw_create_clazz_with_repeat(
     }
 }
 
+pub async fn list_clazz_audit_log(
+    _sudoer: HtySudoerTokenHeader,
+    _host: HtyHostHeader,
+    _auth: AuthorizationHeader,
+    State(db_pool): State<Arc<DbState>>,
+    Query(params): Query<HashMap<String, String>>,
+) -> Json<HtyResponse<Vec<ClazzAuditLog>>> {
+    let result = (|| -> anyhow::Result<Vec<ClazzAuditLog>> {
+        let clazz_id = get_some_from_query_params::<String>("clazz_id", &params)
+            .ok_or_else(|| anyhow!("clazz_id is required"))?;
+        ClazzAuditLog::list_by_clazz_id(
+            &clazz_id,
+            extract_conn(fetch_db_conn(&db_pool)?).deref_mut(),
+        )
+    })();
+    match result {
+        Ok(ok) => wrap_json_ok_resp(ok),
+        Err(e) => {
+            error!("list_clazz_audit_log -> failed, e: {}", e);
+            wrap_json_anyhow_err(e)
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use htycommons::common::current_local_datetime;