src: collapse local var scope in loop

[mertcanaltin]

This change narrows the scope of local variables to within the loop to improve code clarity and reduce the risk of variable misuse. Although purely stylistic, it helps with maintainability.

[nodejs-github-bot]

Review requested:

• @nodejs/config

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.52%. Comparing base (a65421a) to head (5168ceb).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #57626      +/-   ##
==========================================
- Coverage   88.54%   88.52%   -0.03%     
==========================================
  Files         703      703              
  Lines      208545   208545              
  Branches    40216    40222       +6     
==========================================
- Hits       184652   184607      -45     
- Misses      15905    15950      +45     
  Partials     7988     7988              

Files with missing lines	Coverage Δ
src/node_dotenv.cc	84.72% <100.00%> (ø)

... and 25 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[addaleax]

There's no harm in this, but ideally the commit message would describe the motivation for this change as well, esp. since it is a purely stylistic one

[mertcanaltin]

There's no harm in this, but ideally the commit message would describe the motivation for this change as well, esp. since it is a purely stylistic one

Thanks, I edited

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/67304/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/67655/

[mertcanaltin]

Thanks for the review. I'm closing this PR because C++ already optimizes local variables, and the new scope is more appropriate.