feat: add ctxmeta package

[Reasno]

No description provided.

[codecov]

Codecov Report

Merging #188 (aecf7c8) into master (e2be4b3) will increase coverage by 0.10%.
The diff coverage is 86.66%.

@@            Coverage Diff             @@
##           master     #188      +/-   ##
==========================================
+ Coverage   81.40%   81.51%   +0.10%     
==========================================
  Files          83       83              
  Lines        3151     3213      +62     
==========================================
+ Hits         2565     2619      +54     
- Misses        431      437       +6     
- Partials      155      157       +2     

Impacted Files	Coverage Δ
srvhttp/metrics.go	80.64% <ø> (ø)
logging/log.go	39.74% <60.00%> (-0.77%)	⬇️
ctxmeta/ctxmeta.go	90.76% <90.76%> (ø)
config/remote/etcd/etcd.go	79.31% <0.00%> (-6.90%)	⬇️

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