<!-- Describe what has changed in this PR -->
**What changed?**
* Split sync workflow state logic to dedicated file
* SyncActivityState API managing activity state synchronization
* SyncWorkflowState API managing workflow state synchronization
<!-- Tell your future self why have you made these changes -->
**Why?**
Small file, simpler logic
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test? Checked in staging env? -->
**How did you test it?**
existing tests
<!-- Assuming the worst case, what can be broken when deploying this
change to production? -->
**Potential risks**
N/A
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sent to the broader community? (Yes/No) -->
**Is hotfix candidate?**
N/A
