Implement transfer channel upgrades callbacks

[damiannolan]

Summary

Implement the channel upgrade callback handlers for transfer.
Separate PRs can be opened for each callback handler including tests.

The implementation should ensure that the upgrade parameters are compatible with the transfer app.
This includes ordering enforced in ValidateTransferChannelParams as well as version checking, i.e. the upgrade version must be ics20-1.

• OnChanUpgradeInit
• OnChanUpgradeTry
• OnChanUpgradeAck
• OnChanUpgradeOpen
• OnChanUpgradeRestore

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[damiannolan]

Opened #4126 for OnChanUpgradeInit.

[colin-axner]

The OnChanUpgradeAck should also validate the order/version as init/try do

[damiannolan]

Upgrade fields are validated in INIT, TRY and ACK. Now that fields are added to OnChanUpgradeOpen I don't see why we would need to do any extra validation on them. Also, the OnChanUpgradeOpen callback does not have an error return.

Do you think its fine to no-op on OnChanUpgradeOpen in transfer? @colin-axner

[damiannolan]

Closing this as I think all handlers are more or less completed for channel upgradability in transfer. There is working integration test with fee middleware in #4533.

We can open follow ups post-audit if needs be.