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/step9_ml_predict_panel.py

@@ -175,7 +175,7 @@ class Step9MlPredictPanel(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()
@@ -414,8 +414,57 @@ class Step9MlPredictPanel(QWidget):
         if 'output_path' in config:
             self.output_file.set_path(config['output_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
+
+        sampling_csv_path = self.sampling_csv_file.get_path()
+        if not sampling_csv_path:
+            QMessageBox.warning(self, "输入错误", "请选择采样光谱CSV文件！")
+            return
+
+        # 外部模型优先：用户选择了"导入本地预训练模型"
+        if self.use_external_model.isChecked():
+            if not self.external_models_dict:
+                QMessageBox.warning(
+                    self,
+                    "模型未加载",
+                    "请先点击「浏览...」按钮选择模型母文件夹！",
+                )
+                return
+            checked_dict = self._get_checked_models_dict()
+            if not checked_dict:
+                QMessageBox.warning(
+                    self,
+                    "未选择模型",
+                    "请至少勾选一个模型参与预测！",
+                )
+                return
+            config = {
+                'step9_ml_predict': self.get_config(),
+                '_external_models_dict': checked_dict,
+                '_external_model_dir': self.external_model_dir,
+            }
+            global_event_bus.publish('RequestRunSingleStep', {
+                'step_name': 'step9_ml_predict',
+                'config': config,
+            })
+            return
+
+        # 默认流程：使用模型目录
+        models_dir = self.models_dir_file.get_path()
+        if not models_dir:
+            QMessageBox.warning(self, "输入错误", "请选择模型目录！")
+            return
+
+        config = {'step9_ml_predict': self.get_config()}
+        global_event_bus.publish('RequestRunSingleStep', {
+            'step_name': 'step9_ml_predict',
+            'config': config,
+        })
+
     def run_step(self):
-        """独立运行步骤11"""
+        """独立运行步骤11（旧版 parent 链上溯方式，保留兼容）。"""
         sampling_csv_path = self.sampling_csv_file.get_path()
         if not sampling_csv_path:
             QMessageBox.warning(self, "输入错误", "请选择采样光谱CSV文件！")