Add otel tracer

Signed-off-by: Asai Neko <sugar@sne.moe>

main.go

@@ -1,15 +1,30 @@
 package main
 
 import (
+	"context"
+	"log/slog"
 	"nixcn-cms/config"
 	"nixcn-cms/data"
 	"nixcn-cms/logger"
 	"nixcn-cms/server"
+	"nixcn-cms/tracer"
+	"time"
 )
 
 func main() {
 	logger.Init()
 	config.Init()
+
+	ctx := context.Background()
+	shutdown := tracer.Init(ctx)
+	defer func() {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		if err := shutdown(ctx); err != nil {
+			slog.Error("[Main] Tracer shutdown failed!", "err", err)
+		}
+	}()
+
 	data.Init()
 	server.Start()
 }