fix(NcActions): migrate to custom icons in Checkbox and Radio actions

[ShGKme]

☑️ Resolves

• Alternative to fix(NcActionCheckbox): margin around the checkbox #7890
• Use the same icons as in NcCheckboxRadioSwitch instead of legacy server styles
• Specify the focus visible outline.
• Also simplify components a bit
• Both components are very similar, but I don't want to reuse the code to not complicate existing NcActions set. Duplicated code is quite small and simple

🖼️ Screenshots

🏚️ Before	🏡 After

🏁 Checklist

• ⛑️ Tests are included or are not applicable
• 📘 Component documentation has been extended, updated or is not applicable
• 2️⃣ Backport to stable8 for maintained Vue 2 version or not applicable

[ShGKme]

/backport to stable8

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 53.25%. Comparing base (e125565) to head (7feb4ff).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8020   +/-   ##
=======================================
  Coverage   53.25%   53.25%           
=======================================
  Files         101      101           
  Lines        3145     3145           
  Branches      872      872           
=======================================
  Hits         1675     1675           
  Misses       1232     1232           
  Partials      238      238           

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