Preserve Tailwind's default blue color scale

[BeastNectus]

Summary

• rename Solidus Admin's custom blue palette entry to solidus-blue
• keep .body-link using the Solidus brand color through the new namespaced token
• stop shadowing Tailwind's default blue-* color scale in host apps using the Solidus Admin preset

Closes #6405

Notes

Tailwind presets merge theme extensions into the host app. Defining colors.blue as a single hex value removes the default blue-50 through blue-950 scale, so standard utilities such as bg-blue-600 are unavailable. A namespaced token keeps Solidus Admin's brand color without taking over Tailwind's blue scale.

Testing

• node -c admin/config/tailwind.config.js
• git diff --check

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.66%. Comparing base (9956911) to head (8e81562).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6453   +/-   ##
=======================================
  Coverage   89.66%   89.66%           
=======================================
  Files         990      990           
  Lines       20793    20793           
=======================================
  Hits        18645    18645           
  Misses       2148     2148           

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[tvdeyen]

I wonder how the admin tailwind config messes with the frontend TW config (if this is the issue you are trying to solve?)

[tvdeyen]

Ah, I see. We actually extend the Storefronts TW config with our admin theme config. This is not good and should be revisited. But for now, this solves an actual bug. Thank you