fix(sftp): settle direct folder downloads after pause and resume

[binaricat]

Summary

Direct SFTP folder downloads could show Queued while files were transferring. Once paused, resuming could attempt a second directory walk, conflict with the original children, or remain Transferring at 100% after all files reached disk. Use the shared transfer runtime for this entry point and release paused children even after their completed history rows have been compacted.

Type of Change

• Bug fix
• New feature
• Refactor / code cleanup
• Documentation update
• Build / CI change
• Other

Related Issue (optional)

Found during smoke testing of changes since v1.1.82, including #3226 and #3287. No separate issue.

Changes Made

• Register direct downloads as live runtime walks, keep directory status active, and publish final state through the runtime before mirroring it to the panel.
• Keep paused descendant IDs independent of retained UI rows so resume wakes workers whose completed rows were already compacted.
• Derive folder completion counts from the checkpoint and retained children instead of counting a background-completed file again when its invocation settles.
• Add actual hook coverage for pausing discovery with the panel open or unmounted, background completion compaction, exact counts, and no unnecessary reconnect. Add a global-control regression for compacted paused children.

Screenshots / Demo

Actual npm run dev Electron UI on macOS, downloading a 400-file folder from a Linux SSH test host:

1. Download status becomes Transferring and exposes Pause.
2. Pause at 85/400 remains stable; Resume advances normally.
3. Pause again at 367/400, close the SFTP side panel, and resume from the global transfer center.
4. The task reaches Completed, 400 files. All 400 local filenames and file contents match the expected fixture bytes exactly.

The original build reproduced Queued during active transfer. Intermediate repair validation also exposed the lost child pause latch and duplicate count; the final implementation passes the full sequence above.

Testing

• Tested locally with npm run dev, including two pause/resume cycles and panel closure
• npm run lint passes
• npm test passes: 11,478 passed, 18 skipped, 0 failed
• Generated capability tool specs: not applicable
• No new console errors or warnings — not asserted beyond the successful observed flows

180 focused transfer tests passed. The first full-suite run encountered 7 unrelated plugin archive failures because this worktree lacked package-local dependencies and resolved yauzl 2.10 instead of 3.4. After restoring the package dependency layout, the full suite passed with 11,478 passed, 18 skipped, and 0 failed. The new direct-download test uses .test.ts so the normal test command includes it.

A prior full TypeScript comparison reported the same 732 diagnostics on the baseline and fix, with no new normalized diagnostics at that comparison point; this is not a clean typecheck.

Checklist

• Existing project architecture and style followed
• Relevant behavior and validation documented above
• No intentional breaking changes

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-06T08:40:57.233194Z	b2fc27d	Manual request

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[binaricat]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Delightful!

Reviewed commit: b2fc27d168

ℹ️ About Codex in GitHub

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[netcatty-bot]

Codex reported no major issues. This PR is marked ready for human review/merge.