sea: reject trailing content in config JSON

[Archkon]

Ensure the on-demand parser reaches the end of the document after reading the root object. Reject concatenated JSON values with TRAILING_CONTENT

[nodejs-github-bot]

Review requested:

• @nodejs/single-executable

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (54a5095) to head (f2d4b1f).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #64774      +/-   ##
==========================================
- Coverage   90.14%   90.13%   -0.01%     
==========================================
  Files         744      744              
  Lines      242518   242524       +6     
  Branches    45685    45698      +13     
==========================================
- Hits       218611   218609       -2     
- Misses      15396    15432      +36     
+ Partials     8511     8483      -28     

Files with missing lines	Coverage Δ
src/node_sea.cc	89.63% <100.00%> (+0.10%)	⬆️

... and 30 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.