fix: サーバー全体のアップロードサイズ上限とロールポリシーのアップロードサイズ上限に関する修正

[kakkokari-gtyih]

What

• ロールポリシーで解決される maxFileSizeMb では config.maxFileSize が上限となるように
• ロールポリシー設定画面に全体ファイルサイズに関する説明を追加

Why

#17331

Additional info (optional)

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

[github-actions]

このPRによるapi.jsonの差分
差分はありません。
Get diff files from Workflow Page

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 24.83%. Comparing base (408d056) to head (fe6d056).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #17389      +/-   ##
===========================================
+ Coverage    15.22%   24.83%   +9.60%     
===========================================
  Files          247     1155     +908     
  Lines        12322    39307   +26985     
  Branches      4170    10940    +6770     
===========================================
+ Hits          1876     9761    +7885     
- Misses        8183    23678   +15495     
- Partials      2263     5868    +3605     

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[github-actions]

Backend memory usage comparison

Before GC

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	301.30 MB	305.79 MB	+4.48 MB	+1.48%
VmHWM	301.30 MB	305.79 MB	+4.48 MB	+1.48%
VmSize	23078.20 MB	23083.02 MB	+4.81 MB	+0.02%
VmData	1344.74 MB	1349.27 MB	+4.52 MB	+0.33%

After GC

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	301.33 MB	305.80 MB	+4.46 MB	+1.48%
VmHWM	301.33 MB	305.80 MB	+4.46 MB	+1.48%
VmSize	23078.29 MB	23083.27 MB	+4.98 MB	+0.02%
VmData	1344.82 MB	1349.52 MB	+4.69 MB	+0.34%

After Request

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	301.65 MB	306.33 MB	+4.67 MB	+1.55%
VmHWM	301.65 MB	306.33 MB	+4.67 MB	+1.55%
VmSize	23078.29 MB	23083.52 MB	+5.23 MB	+0.02%
VmData	1344.82 MB	1349.77 MB	+4.94 MB	+0.36%

See workflow logs for details