fix: 修复数据库持久化问题，添加dockerignore和启动日志

backend/internal/config/config.go

@@ -1,6 +1,7 @@
 package config
 
 import (
+	"log"
 	"os"
 
 	"github.com/joho/godotenv"
@@ -53,7 +54,7 @@ type SMTPConfig struct {
 var AppConfig *Config
 
 func Load() {
-	godotenv.Load()
+	_ = godotenv.Load()
 
 	AppConfig = &Config{
 		Server: ServerConfig{
@@ -88,6 +89,8 @@ func Load() {
 			From:     getEnv("SMTP_FROM", ""),
 		},
 	}
+
+	log.Printf("Config loaded: DB_DRIVER=%s, DB_FILEPATH=%s", AppConfig.Database.Driver, AppConfig.Database.FilePath)
 }
 
 func getEnv(key, defaultValue string) string {