build: update the development dependencies

[razor-x]

Raises every development dependency to its current major. Runtime dependencies (httpx, httpx-retries, svix) are untouched.

	from	to
black	24.4.2	26.5.1
pylint	3.2.2	4.0.7
astroid	3.2.4	4.0.4
pytest	8.4.2	9.1.1
pytest-cov	5.0.0	7.1.0
mypy	1.19.1	2.3.0
rstcheck	6.2.1	6.3.0

pytest-runner and pytest-watch were already current.

What actually changed, beyond version numbers

black 26 reformats one line — a blank line dropped in seam/route.py. It leaves generated code alone: regenerating and formatting produces no diff under seam/routes or seam/resources, so codegen still writes exactly what is committed.

pylint 4 fixes a latent CI failure. pylint 3.2's astroid cannot resolve collections.abc under Python 3.14, which the lint job runs. Nothing in the tree imports it today, so the failure is invisible — but any file that does would fail lint on a false positive.

Verified rather than assumed

The risk in a pytest major is silently collecting fewer tests, so I measured both on identical code: 87 collected under pytest 8, 87 under pytest 9. No loss.

pylint 4 and mypy 2 each report nothing new: 10.00/10 and clean across 110 files. Full run is 87 passed, with black and rstcheck clean.

Not included

The npm devDependencies are left alone deliberately. @seamapi/types and @seamapi/blueprint drive codegen, so bumping them rewrites the generated SDK surface — an API change wearing a dependency bump's clothing. Worth its own PR where the regenerated diff can be reviewed on its merits. Happy to do that separately.

---

Generated by Claude Code