refactor: persistence singleton and improve backtest cancel performance

[c9s]

No description provided.

[bbgokarma-bot]

Welcome back! @c9s, This pull request may get 246 BBG.

[codecov]

Codecov Report

Merging #750 (19d8013) into main (0e877b7) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main     #750      +/-   ##
==========================================
- Coverage   18.50%   18.49%   -0.01%     
==========================================
  Files         341      341              
  Lines       25761    25766       +5     
==========================================
  Hits         4766     4766              
- Misses      20513    20518       +5     
  Partials      482      482              

Impacted Files	Coverage Δ
pkg/bbgo/activeorderbook.go	0.00% <0.00%> (ø)
pkg/bbgo/environment.go	1.17% <0.00%> (-0.01%)	⬇️
pkg/bbgo/persistence.go	38.35% <ø> (ø)
pkg/bbgo/trader.go	0.00% <0.00%> (ø)

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[bbgokarma-bot]

Hi @c9s,

Well done! 256 BBG has been sent to your polygon wallet. Please check the following tx:

https://polygonscan.com/tx/0x6f318cb2b380d3b7249c85c67f3f7da5a0028eb799bb1299025cb7d623642dc1

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