fix(ipx): always use ipx provider if external baseURL is provided

[danielroe]

🔗 Linked issue

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

it's possible to use a self-hosted ipx instance and in this case we don't need to add an /_ipx handler. And we can support ipx even on non-node targets.

in such a case, this PR avoids setting up the handler and doesn't disable ipx outside a node environment.

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Latest commit:	3e093cc
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commit: 3e093cc

[codecov-commenter]

Codecov Report

❌ Patch coverage is 90.90909% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 62.89%. Comparing base (5dcaea2) to head (3e093cc).
⚠️ Report is 234 commits behind head on main.

Files with missing lines	Patch %	Lines
src/module.ts	85.71%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1800      +/-   ##
==========================================
- Coverage   62.91%   62.89%   -0.02%     
==========================================
  Files          81       81              
  Lines        3772     3776       +4     
  Branches      431      432       +1     
==========================================
+ Hits         2373     2375       +2     
- Misses       1371     1373       +2     
  Partials       28       28              

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