* Add Auth0MCPProvider for Auth0 Auth for MCP
* Document Auth0 MCP provider integration
* Add Auth0MCPProvider scope and auth rejection tests
Cover permissions-based required_scopes enforcement and unauthenticated MCP 401 responses.
* fixed documentation
* Narrow Auth0 docs to integration guide only
* Fix Auth0 provider: use httpx2 instead of httpx
httpx is a dev-only transitive dependency in this repo; runtime installs
declare httpx2 exclusively. The module-level 'import httpx' in auth0.py
broke import on a clean install of fastmcp or fastmcp-slim[server].
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Co-authored-by: Jeremiah Lowin <153965+jlowin@users.noreply.github.com>
