feat: Step1~Step14 面板单步按钮 EventBus 解耦 + Handler 补全（Step8~Step14）+ 旧上帝类删除

- 9 个面板（step1~step6/step8_ml_train/step8_qaa/step9_ml_predict/step10）单步执行按钮从 parent 链上溯改为 global_event_bus.publish('RequestRunSingleStep')

- PipelineExecutor 新增 _on_request_run_single_step 订阅

- 新增 Handler: step8_ml_train / step9_ml_predict / step10_qaa_inversion / step11_concentration / step12_kriging / step13_visualization / step14_report

- 删除旧 water_quality_inversion_pipeline_GUI.py（上帝类已肢解完毕）

src/gui/panels/step5_clean_panel.py

@@ -95,7 +95,7 @@ class Step5CleanPanel(QWidget):
         # 独立运行按钮
         self.run_btn = QPushButton("独立运行此步骤")
         self.run_btn.setStyleSheet(ModernStylesheet.get_button_stylesheet('success'))
-        self.run_btn.clicked.connect(self.run_step)
+        self.run_btn.clicked.connect(self._on_run_single_clicked)
         layout.addWidget(self.run_btn)
 
         layout.addStretch()
@@ -142,8 +142,23 @@ class Step5CleanPanel(QWidget):
         else:
             self.output_file.set_path("")
 
+    def _on_run_single_clicked(self):
+        """通过 EventBus 发布单步执行请求（解耦面板与 PipelineExecutor）。"""
+        from src.gui.core.event_bus import global_event_bus
+
+        csv_path = self.csv_file.get_path()
+        if not csv_path:
+            QMessageBox.warning(self, "输入错误", "请选择水质参数文件！")
+            return
+
+        config = {'step5_clean': self.get_config()}
+        global_event_bus.publish('RequestRunSingleStep', {
+            'step_name': 'step5_clean',
+            'config': config,
+        })
+
     def run_step(self):
-        """独立运行步骤5"""
+        """独立运行步骤5（旧版 parent 链上溯方式，保留兼容）。"""
         csv_path = self.csv_file.get_path()
         if not csv_path:
             QMessageBox.warning(self, "输入错误", "请选择水质参数文件！")