feat: run_command 改为下拉框设置自动/需确认/禁用三种模式

- 替换原有开关为下拉选择框（selectRunCommandMode）
- 新增 setRunCommandMode() 动态控制确认行为
- 需确认模式：弹窗确认后执行
- 自动模式：直接执行，无需确认
- 禁用模式：工具不可用
- 新增 .tool-card-badge.disabled 样式
- 状态从 runCommandEnabled(bool) 迁移为 runCommandMode(string)

src/renderer/services/tool-registry.ts

@@ -356,9 +356,24 @@ export const TOOL_DEFINITIONS: ToolDefinition[] = [
 const CONFIRM_TOOLS = ['run_command'];
 
 export function needsConfirmation(toolName: string): boolean {
+  if (toolName === 'run_command') {
+    // run_command 确认模式由 runCommandMode 状态控制
+    const runCommandMode = (window as any).__runCommandMode || 'confirm';
+    return runCommandMode === 'confirm';
+  }
   return CONFIRM_TOOLS.includes(toolName);
 }
 
+/** 设置 run_command 执行模式 */
+export function setRunCommandMode(mode: 'auto' | 'confirm' | 'disabled'): void {
+  (window as any).__runCommandMode = mode;
+  if (mode === 'disabled') {
+    setToolEnabled('run_command', false);
+  } else {
+    setToolEnabled('run_command', true);
+  }
+}
+
 let enabledTools: Set<string> = new Set([
   'read_file', 'list_directory', 'search_files',
   'write_file', 'create_directory', 'delete_file',