Update endpoints.py

[Belphegor9556]

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Note

Reorganizes endpoint constants in endpoints.py into categorized sections and adds concise documentation without changing paths.

• Endpoints organization (py_clob_client/endpoints.py):
  • Group constants into 5 categorized sections: utility/time, auth/API keys, market data, order management, and account/fees/metadata.
  • Preserve existing endpoint constants/paths while relocating them to appropriate sections (e.g., orders, market data, markets).
  • Add descriptive inline comments for each constant to clarify usage and scope.

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