enhance(frontend): MkDraggable をタッチ操作 (ドラッグ) に対応 (PointerEvents版）

[fruitriin]

What

スマートフォン等のタッチデバイスで MkDraggable による並び替えができるようにする。
PointerEventsに統一する

また、MkPagesで挙動不審になるので、この画面のコンテキストメニューのあしらいを変更する

Why

Fix #17515
Fix #17487

Additional info (optional)

• リグレッションテストは網羅しきれてない

Checklist

• Read the contribution guide
• Test working in a local environment
• (If needed) Add story of storybook
• (If needed) Update CHANGELOG.md
• (If possible) Add tests

[codecov]

Codecov Report

❌ Patch coverage is 1.48515% with 199 lines in your changes missing coverage. Please review.
✅ Project coverage is 15.04%. Comparing base (e50603e) to head (6c6834a).
⚠️ Report is 1 commits behind head on develop.

Files with missing lines	Patch %	Lines
packages/frontend/src/components/MkDraggable.vue	1.48%	146 Missing and 53 partials ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #17535      +/-   ##
===========================================
- Coverage    24.93%   15.04%   -9.90%     
===========================================
  Files         1158      247     -911     
  Lines        39539    12512   -27027     
  Branches     11011     4244    -6767     
===========================================
- Hits          9858     1882    -7976     
+ Misses       23780     8308   -15472     
+ Partials      5901     2322    -3579     

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