[REFERENCE] Sample Link addon imp (Zenodo)

[opaduchak]

This pull request adds a new addon implementation for Zenodo and serves as a reference example for new contributors who want to integrate external services with OSF's addon service.

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What's Included

• ZenodoLinkImp class in addon_imps/link/zenodo.py:

  • Implements the LinkAddonHttpRequestorImp interface.
  • Supports:
    • Listing public depositions and their files.
    • Fetching metadata and building external URLs.
    • Resolving external account identity using the Zenodo API.
    • Mapping Zenodo resource types to SupportedResourceTypes.

• Addon registration in addon_service/common/known_imps.py:

  • Added ZENODO to KnownAddonImps and AddonImpNumbers.

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API Reference

Zenodo API documentation: https://developers.zenodo.org/

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For New Contributors

If you're looking to add support for another external service, this PR is intended as a working template. It shows how to:

• Implement the correct addon interface (LinkAddonHttpRequestorImp)
• Parse and expose resources (e.g., files, metadata, external links)
• Handle pagination and resource mapping
• Register your implementation

Use this PR as a starting point for your own addon. Feel free to fork and adapt it!

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