Estimate swap claim fee requirement

[grod220]

No description provided.

[hdevalence]

This should be fairly straightforward, we can use the current gas prices to estimate the cost of a "pure" swap claim transaction (which will have ~constant size, we can always overestimate a bit), then multiply by the current fee tier (on the assumption that prices won't change dramatically block to block, which seems reasonable).

[jessepinho]

Per @hdevalence in Discord, we'll wait to do this for now since we want to refactor the WasmPlanner a bit first, and the gas prices are all 0 in testnet-preview anyway.

[TalDerei]

outdated as fee logic has changed