chore: unify build system into pyproject.toml

[jansegre]

Motivation

The previous build system was not working very well and wasn't running on this repo.

Acceptance Criteria

• fix some build warnings (optional, separate commit)
• migrate all the configs in setup.cfg, MANIFEST.in, tox.ini, into pyproject.toml
• remove the need to use pkg-config
• update pyproject.toml to current standard
• bump version v0.9.2 -> v0.9.3
• update setup.py with parameters to minimize warnings and remove pkg-config
• add CI matrix to test with several systems (debian, macos, custom build) and several python versions (from 3.10 to 3.13)
• add CI job to build dist wheel (currently not used)