feat: DevTools调试工具 + 前端样式修复 + 管理员登录系统

DevTools (新增):
- 进程管理器: 启动/停止/重启/编译 + 端口自动释放
- 服务接管 (tryAdopt): 检测已运行服务，健康检查通过则直接接管
- 一键启动 (startAllSequential): 按 ai-core→gateway→frontend 顺序启动
- 日志布局切换: 标签页模式 ↔ 三栏并列模式
- 性能监控: CPU/内存采样 + SVG 折线图
- Web UI + WebSocket 实时推送

前端修复:
- tailwind.config.ts: 修复空配置导致 CSS 不加载 (增加 content/colors/fontFamily)
- postcss.config.js: 新建缺失的 PostCSS 配置
- App.tsx: 移除注册功能，仅保留管理员登录 (admin / cyrene-dev-admin)

后端新增:
- config.go: AdminUsername/AdminPassword/RegistrationEnabled 环境变量
- auth_handler.go: 管理员登录 + 注册邮箱验证码 + 注册开关控制
- 管理员凭据: admin / cyrene-dev-admin (默认)

其他:
- .gitignore: 新增 devtools/node_modules/ devtools/logs/ devtools/package-lock.json
- devtools.sh: DevTools 一键启动脚本

backend/ai-core/cmd/main.go

@@ -11,7 +11,7 @@ import (
 	"syscall"
 	"time"
 
-	"github.com/yourname/cyrene-ai/ai-core/internal/context"
+	ctxbuild "github.com/yourname/cyrene-ai/ai-core/internal/context"
 	"github.com/yourname/cyrene-ai/ai-core/internal/llm"
 	"github.com/yourname/cyrene-ai/ai-core/internal/memory"
 	"github.com/yourname/cyrene-ai/ai-core/internal/model"
@@ -72,10 +72,7 @@ func main() {
 	}
 
 	// 初始化上下文构建器
-	ctxBuilder := &context.Builder{}
-
-	// 手动注入 Injector 到 orchestrator（临时方案，后续会用依赖注入框架）
-	personaInjector := &persona.Injector{}
+	ctxBuilder := &ctxbuild.Builder{}
 
 	// 健康检查与对话API的HTTP mux
 	mux := http.NewServeMux()
@@ -85,7 +82,7 @@ func main() {
 
 	// 注册对话API端点
 	mux.HandleFunc("/api/v1/chat", func(w http.ResponseWriter, r *http.Request) {
-		handleChat(w, r, orch, ctxBuilder, llmAdapter, personaLoader, personaInjector, memRetriever, memExtractor)
+		handleChat(w, r, orch, ctxBuilder, llmAdapter, personaLoader, memRetriever, memExtractor)
 	})
 
 	mux.HandleFunc("/api/v1/health", func(w http.ResponseWriter, r *http.Request) {
@@ -165,10 +162,9 @@ func handleChat(
 	w http.ResponseWriter,
 	r *http.Request,
 	_ *orchestrator.Orchestrator,
-	ctxBuilder *context.Builder,
+	ctxBuilder *ctxbuild.Builder,
 	llmAdapter *llm.Adapter,
 	personaLoader *persona.Loader,
-	personaInjector *persona.Injector,
 	memRetriever *memory.Retriever,
 	memExtractor *memory.Extractor,
 ) {
@@ -213,7 +209,7 @@ func handleChat(
 	}
 
 	// 3. 构建对话上下文
-	llmMessages, err := ctxBuilder.Build(ctx, context.BuildParams{
+	llmMessages, err := ctxBuilder.Build(ctx, ctxbuild.BuildParams{
 		UserID:       req.UserID,
 		SessionID:    req.SessionID,
 		UserMessage:  req.Message,
@@ -250,9 +246,12 @@ func handleChat(
 		resp["segments"] = llm.SplitIntoSegments(llmResp.Content)
 	}
 
+	// Ensure unused variables don't cause compile errors
+	_ = personaLoader
+	_ = memRetriever
+	_ = memExtractor
+
 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(resp)
 }
 
-// 确保未使用变量不报错
-var _ = personaInjector