fix(frontend, misskey-js): make block switch work

[saschanaz]

What

1. admin/meta API callを復元
2. metaやinstance情報がないとスイッチを非活性にする
3. タイプの調整

Why

Fixes #11423

Additional info (optional)

@/accountのせいでテストは難しそうですのでタイプエラーだけ直しました

Checklist

• Read the contribution guide
• Test working in a local environment (N/A)
• (If needed) Add story of storybook (N/A?)
• (If needed) Update CHANGELOG.md
• (If possible) Add tests (None)

[codecov]

Codecov Report

Merging #11429 (bc368d7) into develop (5096be0) will increase coverage by 0.01%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop   #11429      +/-   ##
===========================================
+ Coverage    78.75%   78.76%   +0.01%     
===========================================
  Files          920      921       +1     
  Lines        97822    97886      +64     
  Branches      7837     7837              
===========================================
+ Hits         77037    77101      +64     
  Misses       20785    20785              

see 1 file with indirect coverage changes

[syuilo]

🙏🏻