Dropping Python 3.10 support

processing_pyo3 / mewnala declares support for Python 3.10: https://github.com/processing/libprocessing/blob/1d5d4624fbb418d456af36fbef3bf542e2f07cc2/crates/processing_pyo3/pyproject.toml#L18

Python 3.10 is not actively supported since April 2023 and the security support will be ending in October 2026: https://endoflife.date/python

Considering mewnala is a relatively new project and has no worries for backward compatibility, I believe supporting Python 3.10 doesn't worth the effort and it can be dropped easily.

As an extra resource, dropping Python 3.10 complies with

Support for Python versions be dropped 3 years after their initial release.

recommendation from https://scientific-python.org/specs/spec-0000/

从 issue 中链接的 Python 版本声明处的 crates/processing_pyo3/pyproject.toml 开始。更新已声明的支持范围以排除 Python 3.10，然后验证 package metadata 和所有可用的 project checks 是否反映剩余的受支持版本。