Feat/barchart updates

[jsheely]

I'm going to start the process for this PR to make it add more clarity on the issue https://github.com/spectreconsole/spectre.console/issues/1382 raised to see exactly what was changed and to start the conversation

Key points

• Added ValueFormatter for bar chart based on breakdown chart

• Added label color option

• [x] I have read the Contribution Guidelines

• [x] I have commented on the issue above and discussed the intended changes

• [x] A maintainer has signed off on the changes and the issue was assigned to me

• [x] All newly added code is adequately covered by tests

• [x] All existing tests are still running without errors

• [x] The documentation was modified to reflect the changes OR no documentation changes are required.

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Please upvote :+1: this pull request if you are interested in it.

[jsheely]

@microsoft-github-policy-service agree

[patriksvensson]

We will also need to update the documentation so it reflect the new additions.