Restore native touch scrolling in the mobile File Manager

[bifrost0x]

Summary

• let the browser handle native File Manager pan gestures instead of axis-locking them to pan-y
• use touch-action: manipulation so diagonal gesture starts scroll while double-tap zoom stays suppressed
• preserve the existing tap, long-press, selection, and desktop drag-and-drop behavior
• exercise a realistic touch swipe that begins slightly sideways before moving vertically
• bump the File Manager stylesheet cache version

Root cause

The touch regression test added in #177 used a perfectly vertical single-move gesture. With touch-action: pan-y, browsers may reject the complete pan when a real finger starts slightly horizontally, leaving the file list at scrollTop 0.

Validation

• reproduced on merged main: realistic diagonal-start touch gesture failed with scrollTop 0
• fixed regression test: passed with touch-action: manipulation
• JavaScript test files: 35/35 passed
• focused Python/template tests: 37 passed
• File Manager and session workspace Playwright journeys: 22 passed
• ESLint passed
• git diff --check passed

[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 2026-08-31T13:46:50.502873Z	23fb90c	PR opened

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 23fb90ce72

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".