Update project structure page to match docs-starter repo

[fern-api]

Summary

Updates the project structure page so that all file trees, code examples, and descriptions match the actual docs-starter repo.

Key changes:

• Top-level tree: Now shows docs/ folder (containing pages/, assets/, changelog/), snippets/, openapi.yaml and asyncapi.yaml as files (not a folder), styles.css, and generators.yml
• Pages folder: Shows the actual flat list of pages from docs-starter instead of hypothetical nested subfolders
• Assets folder: Shows actual assets (favicon.svg, logo.svg, logo-dark.svg) instead of placeholder files
• docs.yml example: Replaced the buildwithfern.com config with the docs-starter config (tabs, Plant Store API nav, etc.)
• API definitions section: Added an AsyncAPI accordion; updated OpenAPI accordion to show file-based spec references instead of a subfolder approach
• generators.yml example: Now matches docs-starter (openapi.yaml + asyncapi.yaml)
• fern.config.json: Uses "plantstore" org name to match docs-starter

Review & Testing Checklist for Human

• Verify the docs.yml example is a reasonable truncation of the full docs-starter docs.yml (some navigation entries were omitted for brevity — confirm this is acceptable)
• Confirm the page still reads well as a general project structure guide, not just a docs-starter walkthrough — especially for users who use an openapi/ subfolder or Fern Definition
• Check the preview to ensure file trees, code blocks, and accordions render correctly

Test plan: Open the preview link above and compare each section against the docs-starter repo to confirm alignment.

Notes

• The Fern Definition and Multiple APIs accordions were left unchanged since they aren't part of docs-starter's default setup.
• Vale CI passed with 0 errors/warnings/suggestions.

Link to Devin session: https://app.devin.ai/sessions/19146b50b11c43e1bfd1944242aed213

[github-actions]

🌿 Preview your docs: https://fern-preview-fern-update-project-structure.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/docs/getting-started/project-structure

[fern-api]

Requested by: will k
Slack thread: View conversation