docs(design): add headerOnly

[MeteorsLiu]

Design for #434

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.35%. Comparing base (6be2bf5) to head (73e68e4).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #489   +/-   ##
=======================================
  Coverage   84.35%   84.35%           
=======================================
  Files          27       27           
  Lines        2723     2723           
=======================================
  Hits         2297     2297           
  Misses        385      385           
  Partials       41       41           

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[qiniu-x]

[Git-flow] Hi @MeteorsLiu, There are some suggestions for your information:

---

Rebase suggestions

• Following commits seems generated via git merge

  Merge branch 'main' of https://github.com/goplus/llcppg into docs/header-only

Which seems insignificant, recommend to use git rebase command to reorganize your PR.

For other git-flow instructions, recommend refer to these examples.

Details

If you have any questions about this comment, feel free to raise an issue here:

• https://github.com/qiniu/reviewbot