# Batch G Worker B: 3-20 filetree upload target helper

Project root: `/mnt/Data1T/mnote-worktrees/0525-g-worker-b-3-20-filetree-upload-target`

## Goal

Move only the low-risk, synchronous fallback/normalization part of `resolveFileTreeUploadTarget(detail)` out of inline `SIDEBAR_TREE_JS` and into `rust/crates/mnote-web/browser/filetree-runtime.js`.

This is a candidate patch only. Codex will review and selectively merge.

## Allowed files

- `rust/crates/mnote-web/browser/filetree-runtime.js`
- `rust/crates/mnote-web/src/ssr/pages/layout.rs`

Do not edit any other file.

## Expected shape

- Add a small exported runtime helper, for example `resolveFileTreeUploadTargetFallback(detail, deps)` or a better local name.
- Keep async preflight / fetch / backend ownership in `layout.rs`.
- Keep complete inline fallback behavior in `layout.rs`.
- Preserve local-folder resource ownership semantics exactly.
- Do not move `uploadFileToMediaAsset`, `uploadFilesWithResolvedTarget`, `refreshLocalFolderSidebarSnapshot`, or `appendUploadedAssetRow`.

## Verification

Run these from the project root:

```bash
node --check rust/crates/mnote-web/browser/filetree-runtime.js
cargo fmt --manifest-path rust/Cargo.toml --all --check
cargo check --manifest-path rust/Cargo.toml -p mnote-web
cargo test --manifest-path rust/Cargo.toml -p mnote-web filetree -- --test-threads=1
cargo test --manifest-path rust/Cargo.toml -p mnote-web local_upload_runtime_contains_editor_upload_context_helpers -- --test-threads=1
NODE_PATH=/mnt/Data1T/mnote/node_modules node scripts/task479-local-folder-markdown-resource-lifecycle-smoke.js
```

If a command fails because of a pre-existing baseline issue, record the exact command and failure.

## Required output

- Produce `process-handoff.md`, `process-handoff.json`, `result.json`, and `final.md`.
- Include modified files, exact verification commands, pass/fail evidence, risks, and remaining work.
- Do not commit.
- Do not modify `/mnt/Data1T/mnote`.