Summary

Remove the three cloud storage source extensions from the WiredTiger repository: azure_store, gcp_store, and s3_store. These are optional plugins implementing the WT_STORAGE_SOURCE interface for tiered storage, gated behind ENABLE_AZURE, ENABLE_GCP, and ENABLE_S3 CMake flags (off by default).

Motivation

Removing these extensions reduces maintenance burden: each extension carries a large third-party SDK dependency (Azure SDK for C+, google-cloud-cpp, AWS SDK for C+), cloud-specific CI tasks, and ongoing test infrastructure. The core WiredTiger engine has zero coupling to these stores — only documentation and optional build paths reference them.

Scope

Four child tickets cover the work:

• One ticket per cloud storage source (s3, azure, gcp) — removes the extension directory, its SDK cmake wiring, related Evergreen CI tasks, and its test/suite references
• One documentation cleanup ticket — removes remaining references in dist/docs_data.py and src/docs/

What is NOT affected

• Core WiredTiger C code (src/) — no C/header files reference these stores
• dir_store (local filesystem tiered storage) — completely independent
• The WT_STORAGE_SOURCE plugin API itself