fix: 确保数据目录和上传目录存在后再初始化数据库

backend/internal/database/database.go

@@ -11,6 +11,7 @@ import (
 	"context"
 	"fmt"
 	"log"
+	"os"
 	"path/filepath"
 	"time"
 	"verification-platform-backend/internal/config"
@@ -52,6 +53,10 @@ func initDatabase() {
 
 func initSQLite() {
 	dataDir := config.GetDataDir()
+	if err := os.MkdirAll(dataDir, 0755); err != nil {
+		log.Fatal("Failed to create data directory:", err.Error())
+	}
+
 	dbPath := filepath.Join(dataDir, "verification_platform.db")
 
 	var errOpen error