fix asset metadata for fee estimation

[TalDerei]

references #1459

currently, the fee estimation in minifront is hardcoded to use the staking token. Instead, we reconstruct the metadata from the assetId to display the proper token asset. cc @vacekj

---

If the user has UM, the will display the native staking token asset

---

If the user doesn't have UM (simulated by setting the gasFeeToken to extractAltFee in the transaction planner service implementation), it will reconstruct the alternative fee metadata from the assetId.

Currently, the estimated fee is displaying zero since the gas prices are set to zero for that assetId.

---

If gas prices aren't set for a particular assetId, it will error with "GasPrices not available"

[changeset-bot]

⚠️ No Changeset found

Latest commit: ec51e8b

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[vacekj]

lgtm

[github-actions]

Visit the preview URL for this PR (updated for commit ec51e8b):

https://penumbra-ui-preview--pr1468-fee-estimate-denom-n094myqk.web.app

_{(expires Wed, 24 Jul 2024 04:48:47 GMT)}

_{🔥 via Firebase Hosting GitHub Action 🌎}

_{Sign: 709d729610ef7a6369b23f1cb2b820a60cc685b1}

[TalDerei]

requesting additional reviews for assurance after the remote registry work was merged