Python: declare the two integration exports the runtime already serves - #10201

Two optional-integration stubs omit names their runtime already serves, so type checkers reject imports that work.

agent_framework.anthropic:

_IMPORTS: dict[str, tuple[str, str]] = {
    ...
    "RawClaudeAgent": ("agent_framework_claude", "agent-framework-claude"),
}

agent_framework.foundry:

    "FoundryAgentOptions": ("agent_framework_foundry", "agent-framework-foundry"),

Both resolve at runtime through __getattr__, but neither appears in the corresponding __init__.pyi, so ty/mypy/pyright report them as unknown. RawClaudeAgent is also listed in the module docstring's "Supported classes" and belongs to the agent_framework_claude group, which is where the stub's gap shows most clearly:

from agent_framework_claude import ClaudeAgent, ClaudeAgentOptions

Change

• anthropic/__init__.pyi: RawClaudeAgent added to the agent_framework_claude import (the module the runtime maps it to) and to __all__.
• foundry/__init__.pyi: FoundryAgentOptions added to the agent_framework_foundry import and to __all__.

Two files, +4/−1, no runtime code touched.

How these were found

Every __init__.pyi is compared against its __init__.py, both parsed with ast: the stub's symbols are the names in its from … import statements plus __all__; the runtime's are the keys of _IMPORTS when it maps symbol → (module, distribution), or its entries when it is a plain list, plus __all__. Stdlib imports are excluded — without that, from typing import Final in the core stub is reported as a "stub-only export".

After this change the sweep is:

21 in sync; 1 with drift (the typing.Final false positive); 0 unverifiable

Before it, three names were reported: these two, and that false positive. Every other namespace package under python/packages/core matches its stub exactly.

Run against the parent of #10170, the same comparison reproduces the six names that PR added, so it is known to catch this class rather than merely agreeing with the current state.