Feature Request: Show `DispatchInfo` with Extrinsic Decoding

[joepetrowski]

When constructing XCM calls, it's useful to know how much weight you'll need to execute some calls, and perhaps an estimate of the cost of that weight, in order to sufficiently WithdrawAsset and BuyExecution.

The DispatchInfo with weight and partialFee would be a welcome addition to the call details alongside encoded call, encoding details, and call hash.

[jacogr]

While it won't make sense doing this automagically (since the call would be made with each change, aka on debounce), I can see the benefit in having an additional button next to submit for "paymentInfo".