refactor: 移除min_version/base_version_id，后端自动确定基础版本

backend/internal/router/app/info.go

@@ -78,7 +78,7 @@ func handleAppCheckUpdate(c *gin.Context) {
 	}
 
 	hasUpdate := clientVersion != latestVersion.Version
-	if latestVersion.ForceUpdate {
+	if latestVersion.UpdateStrategy == "forced" {
 		hasUpdate = true
 	}
 
@@ -104,7 +104,6 @@ func handleAppCheckUpdate(c *gin.Context) {
 		"update_notes":    latestVersion.Description,
 		"update_strategy": latestVersion.UpdateStrategy,
 		"update_method":   latestVersion.UpdateMethod,
-		"min_version":     latestVersion.MinVersion,
 		"changelog":       latestVersion.Changelog,
 		"files":           files,
 	})