[Refactor](useTheme): singleton pattern

[nonzzz]

Checklist

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• This is WIP now.
• Use singleton pattern refactor useTheme hook.

Change information

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In past, Each hook had its own instance. but refer to #222 . We found is unreasonable.

[codecov]

Codecov Report

Merging #223 (dc13ec9) into master (533e3af) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #223   +/-   ##
=======================================
  Coverage   96.75%   96.75%           
=======================================
  Files         189      189           
  Lines        2126     2126           
  Branches      371      371           
=======================================
  Hits         2057     2057           
  Misses         69       69           

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