fix: thorchain utxo unknown fees

[gomesalexandre]

Description

This PR ensures we get fees estimation back at input time for UTXOs, by leveraging xpub when available. This is after #8079 went in, which made UTXO fees unknown for UTXOs regardless of wallet connected state, and only got the fees on final quote getting before sign and broadcast.

While this was a feature, ops rightly pointed out that it effectively looks and feels like a regression, and if it does so, it probably is.
Fixed by leveraging xpub if handy (i.e if wallet connected) to actually estimate things.

TODO: 

- [x] Test me with and without a wallet connected 
  - [x] ensure this doesn't rug quotes with UTXO sells without a wallet connected 
  - [x] ensure this doesn't rug execution with a wallet connected
- [x] cleanup in a nice enough way so that us deviating from TradeRateInput types with what's effectively a quoteish input isn't too messy

Issue (if applicable)

closes #

Risk

High Risk PRs Require 2 approvals

What protocols, transaction types, wallets or contract interactions might be affected by this PR?

Testing

Engineering

Operations

• 🏁 My feature is behind a flag and doesn't require operations testing (yet)

Screenshots (if applicable)

• No wallet connected

• Wallet connected

https://jam.dev/c/873fc60a-82fe-429f-a274-b99f05553e65

[0xApotheosis]

✅ Gas fee shows for UTXOs when wallet is connected
✅ Gas fee still unknown for UTXOs without wallet connected
✅ Connecting a wallet after getting a UTXO quote correctly fetches the gas fees