Fix estmated fee rendering

[carbolymer]

Changelog

- description: |
    Fix estimated fee rendering: previously the output was of the form `Estimated transaction fee: Coin 357154`.
    Now it is: `Estimated transaction fee: 357154 Lovelace`
# uncomment types applicable to the change:
  type:
  # - feature        # introduces a new feature
  # - breaking       # the API has changed in a breaking way
  # - compatible     # the API has changed but is non-breaking
  # - optimisation   # measurable performance improvements
  # - refactoring    # QoL changes
   - bugfix         # fixes a defect
  # - test           # fixes/modifies tests
  # - maintenance    # not directly related to the code
  # - release        # related to a new release preparation
  # - documentation  # change in code docs, haddocks...

Context

Previously estimated fee was rendered as:

Estimated transaction fee: Coin 357154

After the change:

Estimated transaction fee: 357154 Lovelace

This PR changes also some text highlighting in the help text to make it consistent.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. See Running tests for more details
• Self-reviewed the diff

[smelc]

@carbolymer> LGTM but could you add a golden test that calls the estimate command? I'm surprised we don't track the shape of the output.

[carbolymer]

@smelc I'd have to do this in cardano-testnet, since this is a part of an online command transaction build.

[smelc]

@smelc I'd have to do this in cardano-testnet, since this is a part of an online command transaction build.

@carbolymer> ah I missed that. Nevermind then.