Fleet UI: Script-only package support for macOS

[RachelElysia]

Issue

FE for #33951
Closes #39086

Description

• Update copies from "payload-free" to "script-only package"
• Update .sh copy to include macOS, update icon for .sh and .ps1 to match Figma/existing icons

Screenshots

Testing

• Added/updated automated tests
• QA'd all new/changed functionality manually

[codecov]

Codecov Report

❌ Patch coverage is 27.27273% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.22%. Comparing base (d105fc5) to head (bc9fe1a).
⚠️ Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
...ePage/components/forms/PackageForm/PackageForm.tsx	12.50%	7 Missing ⚠️
...es/hosts/details/DeviceUserPage/DeviceUserPage.tsx	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #39626      +/-   ##
==========================================
- Coverage   66.22%   66.22%   -0.01%     
==========================================
  Files        2433     2433              
  Lines      194903   194904       +1     
  Branches     8454     8453       -1     
==========================================
- Hits       129077   129075       -2     
- Misses      54121    54124       +3     
  Partials    11705    11705              

Flag	Coverage Δ
frontend	54.23% <27.27%> (-0.02%)	⬇️

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