feat: 支持多语言提示词本地化和界面优化

- 添加 prompt_locale 参数支持简体中文、繁体中文和英文提示词本地化
- 移除内置 agents 配置以简化系统架构
- 更新 ContextBuilder 使用动态提示词模板而非硬编码内容
- 在 AgentLoop、Web 接口和 AgentService 中传递 locale 参数
- 添加输出语言指令确保用户界面内容按指定语言生成
- 扩展前端 LanguageSwitcher 组件支持三种语言选项
- 优化 Header 和侧边栏组件的响应式布局和文本截断处理
- 更新测试用例验证不同语言环境下的提示词正确性

app-instance/frontend/components/chat-workbench/AgentTeamBlock.tsx

@@ -6,6 +6,7 @@ import { CheckCircle2, Loader2, Sparkles } from 'lucide-react';
 import type { ProcessArtifact, ProcessEvent, ProcessRun } from '@/types';
 import { Badge } from '@/components/ui/badge';
 import { appArtifactPreview, appFeedRoleLabel, appStatusLabel } from '@/lib/i18n/common';
+import type { AppLocale } from '@/lib/i18n/core';
 import { pickAppText } from '@/lib/i18n/core';
 import { useAppI18n } from '@/lib/i18n/provider';
 import { cn } from '@/lib/utils';
@@ -84,7 +85,7 @@ function buildFeed(
   run: ProcessRun,
   events: ProcessEvent[],
   artifacts: ProcessArtifact[],
-  locale: 'zh-CN' | 'en-US',
+  locale: AppLocale,
 ): AgentFeedItem[] {
   const items: AgentFeedItem[] = [];
   let hasLeadBubble = false;
@@ -152,7 +153,7 @@ function buildFeed(
     .slice(-8);
 }
 
-function runSummary(run: ProcessRun, feed: AgentFeedItem[], locale: 'zh-CN' | 'en-US'): string {
+function runSummary(run: ProcessRun, feed: AgentFeedItem[], locale: AppLocale): string {
   if (run.summary?.trim()) {
     return run.summary.trim();
   }
@@ -262,7 +263,7 @@ function AgentBubble({
   locale,
 }: {
   item: AgentFeedItem;
-  locale: 'zh-CN' | 'en-US';
+  locale: AppLocale;
 }) {
   return (
     <div
@@ -297,7 +298,7 @@ function LiveAgentCard({
   phase: RunCardPhase;
   accentIndex: number;
   onSelect: () => void;
-  locale: 'zh-CN' | 'en-US';
+  locale: AppLocale;
 }) {
   const showSpinner = !TERMINAL_STATUSES.has(run.status);
   const accent = accentFor(accentIndex);
@@ -370,7 +371,7 @@ function ResultCard({
   selected: boolean;
   accentIndex: number;
   onSelect: () => void;
-  locale: 'zh-CN' | 'en-US';
+  locale: AppLocale;
 }) {
   const accent = accentFor(accentIndex);