Add runtime validation

[goccy]

If the internal structure of reflect package changes in the future, it will panic when executing init .

[codecov-commenter]

Codecov Report

Merging #4 into master will decrease coverage by 20.95%.
The diff coverage is 4.76%.

@@             Coverage Diff             @@
##           master       #4       +/-   ##
===========================================
- Coverage   97.41%   76.46%   -20.96%     
===========================================
  Files           5        6        +1     
  Lines         503      650      +147     
===========================================
+ Hits          490      497        +7     
- Misses         12      105       +93     
- Partials        1       48       +47     

Impacted Files	Coverage Δ
init.go	4.76% <4.76%> (ø)

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