fix: 接入备份维护钩子并补齐 SQLX 缓存

- ProcessManager 新增 has_instance_process（备份启动守卫依赖）

- 删除/启动/编辑/迁移目录时接入备份维护钩子（lock_instance_maintenance + begin_instance_deletion + delete_instance_backups），remove_instance 拆出 remove_instance_files_and_state

- run 启动前检查活跃备份操作并加维护锁

- 目录迁移时搬移默认备份仓库并入队清理

- 更新 settings SELECT 的 SQLX 离线缓存（补 ui_font/backup_repository_path/mono_font）

- create_recorded_symlink 非 Windows 未用参数加 cfg_attr 豁免

packages/app-lib/src/api/instance/lifecycle.rs

@@ -103,6 +103,7 @@ pub async fn edit(
     patch: EditInstance,
 ) -> crate::Result<InstanceMetadata> {
     let state = State::get().await?;
+    super::ensure_backup_eligible_edit(instance_id, &patch).await?;
     crate::state::edit_instance(instance_id, patch, &state.pool).await?;
 
     let instance = crate::state::get_instance(instance_id, &state.pool)