Add introduction content and adjust linting

[d33bs]

Description

This PR adds more content to the introduction about what the Almanac will cover and who it's for.

During changes here, I also found I needed to reconfigure vale linting in order for it to work properly (both the poethepoet task and removing write-good.Passive checks as this was emitting false negatives). I also added the branding logo as the almanac logo.

Thanks for any feedback you may have!

Closes #15

What is the nature of your change?

• Content additions or updates (adds or updates content)
• Bug fix (fixes an issue).
• Enhancement (adds functionality).
• Breaking change (these changes would cause existing functionality to not work as expected).

Checklist

Please ensure that all boxes are checked before indicating that this pull request is ready for review.

• I have read the CONTRIBUTING.md guidelines.
• My code follows the style guidelines of this project.
• I have performed a self-review of my own contributions.
• I have commented my content, particularly in hard-to-understand areas.
• I have made corresponding changes to related documentation (outside of book content).
• My changes generate no new warnings.
• New and existing tests pass locally with my changes.
• I have added tests that prove my additions are effective or that my feature works.
• I have deleted all non-relevant text in this pull request template.

[gwaybio]

LGTM! Minor comments and suggestions

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[d33bs]

Thank you @gwaybio ! Merging this in.