feat: 系统优化 - ESLint、Tailwind、前端健壮性、后端工程化、运维可观测性

- 前端: ESLint+Prettier配置、Tailwind v4配置、ErrorBoundary、全局AuthLoader优化、ReactQuery分层
- 后端: MinIO凭证移除、Docker统一为govai品牌、zerolog日志封装、错误码枚举、文件上传校验、单元测试(13项全通过)
- 运维: 健康检查增强(PG/Redis ping)、Prometheus指标(/metrics端点)、多租户tenant包、RateLimit nil防御
- 移动: citation_prompt.txt → internal/assets/

server/cmd/server/router.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/enterprise-ai-platform/server/internal/config"
 	"github.com/enterprise-ai-platform/server/internal/handler"
+	"github.com/enterprise-ai-platform/server/internal/metrics"
 	mw "github.com/enterprise-ai-platform/server/internal/middleware"
 	"github.com/enterprise-ai-platform/server/internal/response"
 	"github.com/enterprise-ai-platform/server/pkg/auth"
@@ -18,6 +19,7 @@ import (
 	"github.com/go-chi/cors"
 	"github.com/jackc/pgx/v5/pgxpool"
 	"github.com/redis/go-redis/v9"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 func newRouter(cfg *config.Config, pool *pgxpool.Pool, rdb *redis.Client) http.Handler {
@@ -83,8 +85,18 @@ func newRouter(cfg *config.Config, pool *pgxpool.Pool, rdb *redis.Client) http.H
 	// Auth middleware
 	requireAuth := mw.Auth(jwtMgr)
 	requireAdmin := mw.RequireRole("admin")
-	// Health check
-	r.Get("/health", handler.HealthCheck)
+	// Prometheus metrics middleware
+	r.Use(func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			metrics.HTTPRequestsTotal.WithLabelValues(r.Method, r.URL.Path, "200").Inc()
+			next.ServeHTTP(w, r)
+		})
+	})
+
+	// Health check and metrics endpoints
+	healthH := handler.NewHealthHandler(pool, rdb)
+	r.Get("/health", healthH.HealthCheck)
+	r.Handle("/metrics", promhttp.Handler())
 
 	// API v1 routes
 	r.Route("/api/v1", func(r chi.Router) {