Add aiohttp support documentation for Python SDK

[devin-ai-integration]

Summary

Adds a new documentation page covering the aiohttp async transport support in Fern-generated Python SDKs (introduced in fern-api/fern#14469, generator v5.3.0). The page is added to the Python section in sdks.yml, placed after "Dynamic authentication" and before the changelog.

The page covers:

• Why aiohttp helps (DNS concurrency bottleneck in httpx.AsyncClient)
• Installation via pip install package[aiohttp]
• Auto-detection behavior (no code changes needed)
• Generated pyproject.toml extras and supporting modules
• CI two-pass testing strategy
• Note on merging with user-defined extras config

Review & Testing Checklist for Human

• Content accuracy: Verify the described behavior (auto-detection via httpx_aiohttp import check, generated _default_clients.py, class names, CI two-pass workflow) matches the actual generator output from feat(python): add aiohttp auto-detection to Python SDK generator fern#14469. This was written from the PR description, not verified against generated code.
• Preview rendering: Check the page renders correctly and the nav link works via the preview deployment URL.
• Audience balance: The page covers both SDK consumer info (install, auto-detection) and SDK maintainer info (generated files, CI config). Confirm this level of detail is appropriate, or if the maintainer sections should be trimmed.

Notes

• Vale style checks pass with zero errors, warnings, or suggestions.
• The page uses generic your-package in installation examples since this is Fern-wide documentation, not customer-specific.

Link to Devin session: https://app.devin.ai/sessions/9ea1b92802014659876c00553ccf6245

[devin-ai-integration]

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[github-actions]

🌿 Preview your docs: https://fern-preview-devin-1775760825-aiohttp-python-docs.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/sdks/generators/python/aiohttp-support