Making the server stack a typing-only import in the client module left
the `Client.server` annotation naming `Server` / `MCPServer`, which
`typing.get_type_hints` can then no longer evaluate: string annotations
are evaluated against the module dict, so a module-level `__getattr__`
would not be consulted either.
Spell the annotation through the `mcp.server` namespace instead. Evaluating
the hints then walks the lazy `mcp` package, which imports `mcp.server` at
that moment only; `import mcp.client` stays free of the server stack and the
evaluated hint is the same union of classes as before. The package's
TYPE_CHECKING mirror now also lists the subpackages that its `__getattr__`
resolves on first access, so type checkers see the same chains.
Max Isbey
5b2530332f