fix: reset visible run logs for new runs

app/gui/tabs/generate.py

@@ -238,7 +238,7 @@ class GenerateTab(QWidget):
 
         self.refresh_cover_templates()
         self.refresh_tasks()
-        self._load_latest_generate_run_log()
+        self._show_current_run_log_empty()
 
     def _set_status(self, message):
         if self.status_callback is not None:
@@ -253,6 +253,16 @@ class GenerateTab(QWidget):
         scroll_bar = self.run_log_view.verticalScrollBar()
         scroll_bar.setValue(scroll_bar.maximum())
 
+    def _show_current_run_log_empty(self):
+        self.run_log_view.setPlainText("本轮日志会在开始运行后显示")
+
+    def _reset_generate_run_log(self, tasks, generate_cover):
+        self.run_log_view.clear()
+        cover_text = "是" if generate_cover else "否"
+        self._append_generate_log(
+            f"本轮AI生成开始：任务 {len(tasks)} 条，生成封面：{cover_text}"
+        )
+
     def _on_generate_cover_toggled(self, checked):
         previous = bool(appconfig.ai_config(self.config).get("generate_cover", False))
         if self._save_generate_cover_setting(show_status=True):
@@ -478,7 +488,7 @@ class GenerateTab(QWidget):
         worker.failed.connect(self._on_generate_failed)
         worker.finished.connect(self._on_generate_finished)
         worker.cancelled.connect(self._on_generate_cancelled)
-        self.run_log_view.clear()
+        self._reset_generate_run_log(tasks, generate_cover)
         thread = run_worker(worker, thread_name="GenerateWorker", start=False)
         thread.finished.connect(lambda: self._forget_generate_thread(thread))
         self.generate_worker = worker
@@ -641,7 +651,6 @@ class GenerateTab(QWidget):
     def _on_generate_finished(self, payload):
         self._set_generate_running(False)
         self.refresh_tasks()
-        self._load_latest_generate_run_log()
         self._update_generate_progress(payload)
         if payload.get("error"):
             self._set_status(f"AI 生成失败：{payload.get('error')}")
@@ -651,7 +660,6 @@ class GenerateTab(QWidget):
     def _on_generate_cancelled(self, payload):
         self._set_generate_running(False)
         self.refresh_tasks()
-        self._load_latest_generate_run_log()
         self._update_generate_progress(payload)
         self._set_status("AI 生成已停止：" + self._generate_progress_text(payload))