feat: add basic api for log

[sysulq]

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[codecov-commenter]

Codecov Report

Merging #379 (5fe507e) into master (771ae2a) will increase coverage by 0.05%.
The diff coverage is 9.09%.

@@            Coverage Diff             @@
##           master     #379      +/-   ##
==========================================
+ Coverage   40.06%   40.11%   +0.05%     
==========================================
  Files          84       84              
  Lines        5551     5571      +20     
==========================================
+ Hits         2224     2235      +11     
- Misses       3169     3177       +8     
- Partials      158      159       +1     

Impacted Files	Coverage Δ
pkg/xlog/log.go	72.05% <ø> (ø)
pkg/xlog/api.go	16.66% <9.09%> (-83.34%)	⬇️
pkg/store/gorm/logger.go	37.50% <0.00%> (+22.91%)	⬆️

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