feat(core): import progress & perf (#15197)

#### PR Dependency Tree


* **PR #15197** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added a new import pipeline with “plan then commit” batch handling for
Markdown, Notion HTML, Obsidian, and Bear backups.
* Enabled native import sessions with progress, cancellation, and
batch-by-batch committing (including assets, folders, icons, and tags).
  * Added web preflight limits for ZIP and multi-file imports.
* **Bug Fixes**
* Improved import error/warning reporting and continued processing when
some items fail.
* Strengthened snapshot-based file/directory picking to preserve paths.
* **Chores**
  * Updated project packaging/configuration for the new import workflow.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/native/src/lib.rs

@@ -1,4 +1,5 @@
 pub mod hashcash;
+mod import_session;
 #[cfg(not(any(target_os = "android", target_os = "ios")))]
 pub mod preview;
 
@@ -10,3 +11,4 @@ static ALLOC: mimalloc::MiMalloc = mimalloc::MiMalloc;
 pub use affine_media_capture::*;
 pub use affine_nbstore::*;
 pub use affine_sqlite_v1::*;
+pub use import_session::*;