feat: add PYBIND11_NOINLINE_ATTR and PYBIND11_INLINE macros Decompose PYBIND11_NOINLINE into the attribute part plus inline, and add PYBIND11_INLINE, which becomes empty under PYBIND11_PRECOMPILED. Groundwork for optional pre-compilation; all current expansions are unchanged and PYBIND11_INLINE is not used yet. Assisted-by: ClaudeCode:claude-fable-5