feat: External liquidity integration

[rbajollari]

Description

closes: #XXXX

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Author Checklist

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I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• added appropriate labels to the PR
• targeted the correct branch
• provided a link to the relevant issue or specification
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
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Reviewers Checklist

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• confirmed the correct type prefix in the PR title
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• reviewed state machine logic
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• reviewed tests and test coverage
• manually tested (if applicable)