feat: add distributed backend selection and safe query hashing

[mheidari988]

auto-select distributed cache when available or requested, expose cache backend option, and introduce ICacheKeyProvider with hash failure fallback to avoid pipeline breaks. include tests/docs for new behavior.

Summary

• What does this change do?

Testing

• dotnet test
• Other (add details):

Checklist

• Includes docs/changelog updates if user-facing
• Adds/updates tests
• Keeps public API surface minimal and backward compatible (or documents breaking change)
• PR scoped to a single concern/module where possible

Notes

• Breaking changes? If yes, describe impact and migration.
• Related issues/links: