fix: 修复跨实例同步移植的首轮编译错误

- re-export 可见性：synced_options_path 改从 files 导入；SyncedOptionJoinResolution 改从 pending 导入

- bind 移动语义：18 处 .bind(x) 改为 .bind(&x)（metadata.instance.id / option_id / custom_id 等）

- storage.rs：SqliteRow 字段访问改为 row.get()

- modpack.rs：去掉 Axolotl 独有的 DownloadMeta/DownloadReason，改用本地 5 参数 fetch

- state/mod.rs：补齐第 2 处 State 初始化的新增字段

packages/app-lib/src/api/instance/synced_options/hotbars.rs

@@ -3,10 +3,11 @@ use super::files::{
     CheckpointStatus, begin_checkpoint, checkpoint, ensure_link,
     finish_checkpoint, instance_game_dir, nbt_from_bytes, nbt_to_bytes,
     read_nbt_file, safe_instance_id, sha1_bytes, sha1_file,
+    synced_options_path,
 };
 use super::orchestration::{
     backup_bytes, create_synced_directories, option_effective,
-    seed_from_instance, synced_options_path,
+    seed_from_instance,
 };
 use crate::state::{InstanceMetadata, SyncedOption};
 use crate::util::io;