Add changelog entry for Python library docs generation

[devin-ai-integration]

Add changelog entry for Python library docs generation

Summary

Adds a new CLI changelog entry (v3.86.0) documenting the Python library docs generation feature. The entry describes the end-to-end workflow: configuring a libraries section in docs.yml, running fern generate --docs, and the underlying pipeline where the CLI sends the repo URL to FDR for parsing, then downloads the resulting IR to produce local MDX pages.

The entry includes two YAML configuration examples showing how to define a library and reference it in navigation.

Review & Testing Checklist for Human

• Verify version number: The entry uses 3.86.0 (minor bump from 3.85.6). Confirm this matches the actual released CLI version for this feature.
• Check changelog verbosity: This entry is significantly longer than typical entries in the CLI changelog (most are 1-3 lines). Consider whether it should be trimmed to match existing conventions.
• Validate configuration examples: The libraries config and - library: navigation YAML examples were derived from source code/tests — confirm they match the actual supported schema.
• Confirm date: Entry is added to 2026-02-24.mdx. Verify the feature shipped on this date.

Notes

Requested by: Fern Support
Link to Devin run

[devin-ai-integration]

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[dsinghvi]

Requested by: Fern Support
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[github-actions]

🌿 Preview your docs: https://fern-preview-196e8a66-9552-44ef-a7ea-0aea5e47e4bb.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/cli-api-reference/cli-reference/changelog/2026/2/24
• learn/dashboard/getting-started/overview
• learn/docs/preview-publish/publishing-your-docs