[Feature] Migrate from MkDocs to Zensical

[liblaf]

🥰 Feature Description

some features that I think would be useful:

• Support mkdocs-api-autonav plugin functionality zensical/backlog#7
• Support mkdocs-gen-files plugin functionality zensical/backlog#8
• Proposal: Configuration zensical/backlog#47
• More flexible defaults for Markdown extensions zensical/backlog#70
• Configuration override via environment variables zensical/backlog#90 --- We must have this if we want to deploy docs to multiple hosts, e.g. GitHub Pages and Read the Docs.

🧐 Proposed Solution

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📝 Additional Information

No response