v2.4.2 — Benchmark

A surveyor's benchmark is a reference mark — a fixed point of known position, cut into rock, that everything else can be measured against. This release is exactly that: no new user-visible features, but the Sphinx extension is now covered by an end-to-end integration test, so what was previously advertised is now verified.

Thanks to @BlocksecPHD for contributing the test (#124, closes #114).

Internal

• Build system migrated from hatchling+uv to PDM (pdm-backend). No user-visible changes; pip install pyan3 works as before.
• Sphinx extension: end-to-end integration test covering sphinx-build, the .. callgraph:: directive, pan/zoom HTML wiring, and directive option propagation. Uses an in-test dot stub, so CI needs no system Graphviz. Closes #114. (#124 — thanks @BlocksecPHD)

See CHANGELOG.md for the full history.