Add better error propagation to EVM permits

Currently we only have custom error: x and possibly nonce/fee errors
We need to be able to display proper errors to the user. Propagate the errors from permits to error message.

i.e. `custom error: XXXYYY` where XXX = pallet index (if EVM error then 999) and YYY = error Id.

Add a way to get EVM errors - either build them to JSON so we can grab them from FE or get by RPC. (pallet errors are already in metadata)

Start by tracing how EVM permits currently propagate custom, nonce, and fee errors. Compare exposing EVM errors as JSON for the frontend with retrieving them by RPC, while preserving pallet errors from metadata; done when users can identify the pallet index and error ID, including EVM error index 999.

Written by the indexing model from the issue text.