Testnet deployment prep

[sisyphusSmiling]

Related: #102

Description

• Adds USDCFlow contract which will be needed for TokenHandler configuration on initialization
• Update flow.json with necessary aliases and accounts
• Adds CadenceNativeTokenHandler configuration to main.go initialization script
• Sets bridge as paused on deployment
• Add batch onboarding queries as requested by @nialexsan for user in Flow Port
• Updates Previewnet import addresses in import and update code args
• Adds Testnet code args to be committed to FlowEVMBridgeTemplates during bridge configuration

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For contributor use:

• Targeted PR against main branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the standards mentioned here.
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.33%. Comparing base (dff784b) to head (efc69c1).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #106   +/-   ##
=======================================
  Coverage   86.33%   86.33%           
=======================================
  Files          17       17           
  Lines         922      922           
=======================================
  Hits          796      796           
  Misses        126      126           

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