feat: Refactor service management scripts to use a unified dev script

- Added package.json to manage development scripts.
- Updated restart-services.ps1 to call the new dev script for starting services.
- Refactored start-admin.ps1, start-backend.ps1, start-frontend.ps1, and start-mcp.ps1 to utilize the dev script for starting respective services.
- Enhanced stop-services.ps1 to improve process termination logic by matching command patterns.

backend/assets/views/admin/site_settings.html

@@ -88,12 +88,12 @@
         </div>
         <div class="field">
             <label>聊天 API Base</label>
-            <input name="ai_api_base" value="{{ form.ai_api_base }}" placeholder="http://localhost:8317/v1">
+            <input name="ai_api_base" value="{{ form.ai_api_base }}" placeholder="https://91code.jiangnight.com/v1">
         </div>
         <div class="field field-wide">
             <label>聊天 API Key</label>
-            <input name="ai_api_key" value="{{ form.ai_api_key }}" placeholder="your-api-key-1">
-            <div class="field-hint">这里只保存在后端数据库里，前台公开接口不会返回这个字段。当前默认接入本地 NewAPI 网关，未配置时前台仍可做本地检索，但不会生成完整聊天回答。</div>
+            <input name="ai_api_key" value="{{ form.ai_api_key }}" placeholder="sk-...">
+            <div class="field-hint">这里只保存在后端数据库里，前台公开接口不会返回这个字段。当前默认接入 91code.jiangnight.com 的 NewAPI 兼容接口，未配置时前台仍可做本地检索，但不会生成完整聊天回答。</div>
         </div>
         <div class="field">
             <label>聊天模型</label>