fix(core): 优化模型初始化策略，保护用户自定义配置不被覆盖

- 改进ModelManager初始化逻辑，仅在缺失元数据时补齐默认值
- 增强连接测试功能，提升配置验证和错误处理
- 新增测试用例验证配置保护机制的有效性

Author: linshenkx

packages/core/src/services/model/manager.ts

@@ -107,25 +107,24 @@ export class ModelManager implements IModelManager {
               const existingModel = updatedModels[key];
 
               if (isTextModelConfig(existingModel)) {
-                // 已经是新格式，保留用户配置
-                const updatedModel = {
-                  ...defaultConfig,
-                  // 保留用户的启用状态和连接配置
-                  enabled: existingModel.enabled !== undefined ? existingModel.enabled : defaultConfig.enabled,
-                  connectionConfig: {
-                    ...defaultConfig.connectionConfig,
-                    ...(existingModel.connectionConfig || {})
-                  },
-                  paramOverrides: {
-                    ...defaultConfig.paramOverrides,
-                    ...(existingModel.paramOverrides || {})
-                  }
-                };
-
-                if (JSON.stringify(updatedModels[key]) !== JSON.stringify(updatedModel)) {
+                // 已经是新格式，保留用户配置，仅在缺失关键字段时补齐默认值
+                const updatedModel = { ...existingModel } as TextModelConfig;
+                let patched = false;
+
+                if (!updatedModel.providerMeta && defaultConfig.providerMeta) {
+                  updatedModel.providerMeta = defaultConfig.providerMeta;
+                  patched = true;
+                }
+
+                if (!updatedModel.modelMeta && defaultConfig.modelMeta) {
+                  updatedModel.modelMeta = defaultConfig.modelMeta;
+                  patched = true;
+                }
+
+                if (patched) {
                   updatedModels[key] = updatedModel;
                   hasUpdates = true;
-                  console.log(`[ModelManager] Updated default model: ${key}`);
+                  console.log(`[ModelManager] Patched missing metadata for model: ${key}`);
                 }
               } else if (isLegacyConfig(existingModel)) {
                 // 旧格式，尝试使用 Registry 转换为新格式

packages/core/tests/unit/model/manager.test.ts

@@ -101,6 +101,45 @@ describe('ModelManager', () => {
     });
   });
 
+  describe('initialization behavior', () => {
+    it('should not overwrite existing model metadata or connection settings when reinitialized', async () => {
+      const targetId = 'openai';
+      const existing = await modelManager.getModel(targetId);
+      expect(existing).toBeDefined();
+
+      const customProviderMeta = {
+        ...existing!.providerMeta,
+        name: 'Custom Provider Name'
+      };
+
+      const customModelMeta = {
+        ...existing!.modelMeta,
+        id: 'custom-openai-model',
+        name: 'Custom OpenAI Model'
+      };
+
+      const customBaseURL = 'https://custom-openai.example.com/v1';
+
+      await modelManager.updateModel(targetId, {
+        providerMeta: customProviderMeta,
+        modelMeta: customModelMeta,
+        connectionConfig: {
+          ...existing!.connectionConfig,
+          baseURL: customBaseURL
+        }
+      });
+
+      const secondRegistry = new TextAdapterRegistry();
+      const reloadedManager = new ModelManager(storageProvider, secondRegistry);
+      const reloaded = await reloadedManager.getModel(targetId);
+
+      expect(reloaded?.providerMeta.name).toBe('Custom Provider Name');
+      expect(reloaded?.modelMeta.id).toBe('custom-openai-model');
+      expect(reloaded?.modelMeta.name).toBe('Custom OpenAI Model');
+      expect(reloaded?.connectionConfig.baseURL).toBe(customBaseURL);
+    });
+  });
+
   describe('getModel', () => {
     it('should retrieve an existing model by key', async () => {
       const model = createTextModelConfig('MyModel', 'MyModel');

packages/ui/src/composables/useTextModelManager.ts

@@ -569,33 +569,45 @@ export function useTextModelManager() {
     formConnectionStatus.value = { type: 'info', message: t('modelManager.testing') }
 
     try {
-      // 获取原始配置
-      const existingConfig = await modelManager.getModel(editingModelId.value)
+      const existingConfig = editingModelId.value ? await modelManager.getModel(editingModelId.value) : undefined
       if (!existingConfig) {
         throw new Error('模型配置不存在')
       }
 
-      // 创建临时测试配置，使用当前表单的参数覆盖
-      // 注意：如果 API Key 被脱敏显示，需要使用原始 Key
-      const connectionConfig = {
+      if (!form.value.providerId || !form.value.modelId) {
+        throw new Error('模型未选择')
+      }
+
+      const providerMeta = ensureProviderMeta(form.value.providerId, existingConfig.providerMeta)
+      const modelMeta = ensureModelMeta(form.value.providerId, form.value.modelId, existingConfig.modelMeta)
+
+      const baseURL = typeof form.value.connectionConfig?.baseURL === 'string'
+        ? form.value.connectionConfig.baseURL.trim()
+        : undefined
+
+      const connectionConfig: TextConnectionConfig = {
+        ...existingConfig.connectionConfig,
         ...form.value.connectionConfig,
+        baseURL: baseURL || existingConfig.connectionConfig?.baseURL,
         apiKey: form.value.displayMaskedKey && form.value.originalApiKey
           ? form.value.originalApiKey
           : form.value.connectionConfig.apiKey
       }
 
+      if (!connectionConfig.apiKey && existingConfig.connectionConfig?.apiKey) {
+        connectionConfig.apiKey = existingConfig.connectionConfig.apiKey
+      }
+
       const tempConfig: TextModelConfig = {
-        ...existingConfig,
-        id: `temp-test-${editingModelId.value}`,
+        id: `temp-test-${editingModelId.value}-${Date.now()}`,
         name: form.value.name,
         enabled: form.value.enabled,
-        providerMeta: { ...existingConfig.providerMeta },
-        modelMeta: { ...existingConfig.modelMeta },
+        providerMeta,
+        modelMeta,
         connectionConfig,
         paramOverrides: { ...(form.value.paramOverrides || {}) }
       }
 
-      // 创建临时模型用于测试
       await modelManager.addModel(tempConfig.id, tempConfig)
 
       try {