fix: properly merge PR #415 tap & hold feature

[masonfox]

Summary

Fixes PR #415 which was marked as MERGED in GitHub but the commits never actually made it into the develop branch. This PR cherry-picks the three orphaned feature commits to restore the tap & hold to select functionality.

Problem: PR #415 shows as merged, but the feature code is missing from develop (except for useLongPress.ts which was added separately in commit 9f2ca50).

Solution: Cherry-picked the three orphaned commits and squashed them into a single commit with proper attribution.

---

Changes

Modified Files (5)

1. hooks/useBookListView.ts - Added enterSelectModeWithSelection() function
2. components/Books/BookListItem.tsx - Integrated useLongPress hook + keyboard accessibility
3. components/Books/DraggableBookList.tsx - Added long-press props and wiring
4. app/shelves/[id]/page.tsx - Wired up long-press handlers to list views

New Files (1)

5. __tests__/hooks/useLongPress.test.ts - Comprehensive test suite (22 tests)

Note: hooks/useLongPress.ts already existed on develop (added by commit 9f2ca50) and matches the final PR version, so it was kept unchanged.

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Feature: Tap & Hold to Select

Implements long-press gesture to enter select mode on shelf items, eliminating the need to scroll to the top to press the "Select" button.

Key Features:

• Long-press (500ms) on book card body enters select mode and auto-selects the item
• Separate touch targets: drag handle (200ms) vs card body (500ms) to avoid conflicts
• 10px movement tolerance to prevent activation during scrolling
• Keyboard accessibility: Space and Enter keys trigger selection
• ARIA attributes for screen readers
• Mobile-focused UX improvement

Behavior:

1. User long-presses on book card (NOT in select mode)
2. After 500ms: enters select mode + selects that book
3. BulkActionBar appears at bottom
4. User can tap other books to select/deselect
5. Existing "Select" button still works

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Testing

✅ All 4044 tests pass (includes 22 new useLongPress tests)
✅ Build succeeds with no TypeScript errors

Test Coverage

• Mouse events (down, up, move, leave)
• Touch events (start, end, cancel, move)
• Keyboard events (Space, Enter)
• Movement tolerance (cancels when exceeding 10px)
• Configurable delay and tolerance options
• Memory leak prevention (cleanup on unmount)
• ARIA attributes for accessibility

---

Original Commits

This PR incorporates the following orphaned commits:

• b88e3fc - feat: implement tap & hold to select shelf items
• 990c8aa - fix: implement @review feedback (iteration 1)
• f623bb4 - fix: add onTouchCancel handler and Enter key accessibility support

---

References

• Original PR: feat: implement tap & hold to select shelf items #415
• Issue: Tap & hold to select shelf item #414
• Problem Commit: 9f2ca50 (added useLongPress.ts but not integration code)

Resolves: #414
Fixes: #415

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

@@             Coverage Diff             @@
##           develop     #419      +/-   ##
===========================================
+ Coverage    78.70%   78.82%   +0.12%     
===========================================
  Files          167      168       +1     
  Lines         7559     7607      +48     
  Branches      1850     1860      +10     
===========================================
+ Hits          5949     5996      +47     
  Misses        1127     1127              
- Partials       483      484       +1     

Flag	Coverage Δ
unittests	78.82% <ø> (+0.12%)	⬆️

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[masonfox]

@copilot /review

[Copilot]

@copilot /review

Ran review checks on commit 3409496: PR workflow run 24510256705 is green (tests + Docker build), targeted long-press tests pass locally (22/22), and build succeeds. No additional code changes were required.

UI screenshot: N/A (no UI changes made in this review pass).