chore(docs): add example for densities prop usage

[Afshar07]

🔗 Linked issue

resolves #1465

❓ 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

Improve the densities prop documentation with clearer explanations and a better example showing how pixel multiplication works.

[vercel]

@Afshar07 is attempting to deploy a commit to the NuxtLabs Team on Vercel.

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[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@nuxt/image@1937

commit: 04490fa

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (main@43f2b28). Learn more about missing BASE report.

Additional details and impacted files

@@          Coverage Diff           @@
##             main   #1937   +/-   ##
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  Coverage        ?   7.08%           
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  Files           ?      76           
  Lines           ?    3531           
  Branches        ?     137           
======================================
  Hits            ?     250           
  Misses          ?    3234           
  Partials        ?      47           

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