[docs] restrict sphinx

[piotrkluba]

Note

Low Risk
Dependency-only change scoped to the optional docs toolchain; main runtime dependencies and application logic are unaffected.

Overview
Restricts the optional docs dependency sphinx from >=7 to >=7,<9 in pyproject.toml to avoid pulling Sphinx 9.x.

Regenerates poetry.lock (now with Poetry 2.2.1), which collapses several docs-only dependency entries/markers (e.g., sphinx, docutils, sphinx-autodoc-typehints, autodocsumm) and adjusts some platform/python markers and version spec formatting to match the new resolution.

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