feat(category): implement recategorize backfill engine and fallback mapping (Spec §3.4-3.5 A4-A5)

cmd/recategorize/main.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"os"
+	"time"
+
+	"chat-agent-system/internal/bizdev"
+	"chat-agent-system/internal/config"
+)
+
+func main() {
+	envPath := flag.String("env", ".env", "环境配置文件路径")
+	sessionID := flag.String("session", "", "指定处理的会话ID (留空则全量回填)")
+	flag.Parse()
+
+	cfg, err := config.Load(*envPath)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "加载配置失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	svc := bizdev.NewService(cfg)
+	ctxMgr := svc.ContextManager()
+	if ctxMgr == nil {
+		fmt.Fprintf(os.Stderr, "ContextManager 未初始化\n")
+		os.Exit(1)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
+	defer cancel()
+
+	fmt.Println("==================================================================")
+	fmt.Println("   🔄 历史消息分类回填与数据对齐工具 (Spec §3.4 A4)   ")
+	fmt.Println("==================================================================")
+	if *sessionID != "" {
+		fmt.Printf("处理目标会话: %s\n", *sessionID)
+	} else {
+		fmt.Println("处理目标: 全量历史消息")
+	}
+
+	res, err := ctxMgr.RecategorizeMessages(ctx, *sessionID)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "分类回填失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	fmt.Printf("✅ 分类回填完成!\n已扫描消息数: %d\n已更新分类数: %d\n", res.TotalProcessed, res.TotalUpdated)
+}