http: increase keepAliveTimeout default to 65 seconds

[pimterry]

This PR takes the code from #59203 (now stalled) and fixes it up to get the tests & linting passing so we can hopefully merge just in time for v26. Conclusion there I think it this is possibly semver-major, we're not 100% sure but better to release with a major bump initially at least.

See discussion there for context. I've kept @pras529 as a co-author on the commit.

[nodejs-github-bot]

Review requested:

• @nodejs/http
• @nodejs/net

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.68%. Comparing base (2071c44) to head (a110f7e).
⚠️ Report is 11 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #62782      +/-   ##
==========================================
- Coverage   89.68%   89.68%   -0.01%     
==========================================
  Files         706      706              
  Lines      218143   218191      +48     
  Branches    41732    41741       +9     
==========================================
+ Hits       195650   195693      +43     
- Misses      14402    14423      +21     
+ Partials     8091     8075      -16     

Files with missing lines	Coverage Δ
lib/_http_server.js	97.06% <100.00%> (-0.22%)	⬇️

... and 48 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/72731/