Refactor state and trie integration

[weiihann]

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[codecov]

Codecov Report

Attention: Patch coverage is 70.05095% with 823 lines in your changes missing coverage. Please review.

Project coverage is 70.79%. Comparing base (f9b4aed) to head (2701f26).

Files with missing lines	Patch %	Lines
core/state/state.go	63.22%	105 Missing and 48 partials ⚠️
core/trie2/proof.go	68.02%	103 Missing and 38 partials ⚠️
core/trie2/trieutils/bitarray.go	74.48%	131 Missing and 4 partials ⚠️
core/trie2/trie.go	79.10%	61 Missing and 18 partials ⚠️
core/state/history.go	10.00%	53 Missing and 1 partial ⚠️
core/state/contract.go	71.89%	35 Missing and 17 partials ⚠️
core/trie2/node_enc.go	58.55%	31 Missing and 15 partials ⚠️
core/trie2/triedb/pathdb/database.go	63.91%	26 Missing and 9 partials ⚠️
core/trie2/node.go	44.23%	29 Missing ⚠️
blockchain/state.go	59.61%	14 Missing and 7 partials ⚠️
... and 14 more

Additional details and impacted files

@@                       Coverage Diff                       @@
##           weiihann/improve-state-trie    #2535      +/-   ##
===============================================================
- Coverage                        73.61%   70.79%   -2.82%     
===============================================================
  Files                              136      150      +14     
  Lines                            16658    18193    +1535     
===============================================================
+ Hits                             12262    12879     +617     
- Misses                            3535     4452     +917     
- Partials                           861      862       +1     

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