v0.4.0 — a graph's constants are parameters

MADDENING 0.4.0 makes a graph's constants data:

• Parameters. Node constants are parameters that jax.grad reaches and that change without a recompile.
• System identification. maddening.sysid fits those parameters to recorded data.
• Interface mappings. They couple nodes whose grids do not match.
• FMU export. A graph exports as a working FMI 3.0 FMU.
• Coupling groups. They now stop at a tolerance and report how far from the fixed point they may be.

Upgrading: 0.4.0 needs Python 3.12 or later and JAX 0.10 or 0.11. Neither range overlaps 0.3.1's, so plan the JAX migration before you install. The release notes have "What changes for existing code" and an upgrade checklist.

• Release notes: docs/release_notes/v0.4.0.md
• Changelog: CHANGELOG.md [0.4.0]
• Known anomalies: the release notes' "Known anomalies" section; the registry is docs/validation/known_anomalies.yaml
• How the release was built and checked: the development record

Assets: the four CycloneDX SBOMs, one for each covered install (core, server, surrogates, usd), generated from this tag's tree. See docs/validation/soup_package.md §6.