fix: allow JAX 0.11 downstream environments

[AHMETHAKANBEZIR1]

Summary

Fixes #801.
Remove the JAX/JAXlib <0.11 bounds so a downstream project can select JAX 0.11. Refresh only these two packages in uv.lock, regenerate asv-constraints.txt, and add an Unreleased note. The lock selects 0.11.2 for Python >=3.12 and retains 0.10.2 for Python 3.11. No Python implementation, test, or CI configuration is changed.

Validation

• A real uv pip compile with downstream constraints jax>=0.11 and jaxlib>=0.11 fails against the base metadata and resolves against this metadata.
• Configured uv run poe test: 3229 passed, 1 existing skip on Windows CPU in Python 3.12 and Python 3.13 with JAX/JAXlib 0.11.2. The source was imported from this checkout.
• uv run poe lint-ci: all 156 files pass. poe all-tests also passed its 41 docstring examples before reaching the ASV environment failure described below.
• uv build --wheel and installation of that wheel with JAX/JAXlib 0.11.2 into a fresh Python 3.12 environment pass. The installed package runs a JIT exact-GP posterior mean example (NumPy 2.5.3, NumPyro 0.22.0, Equinox 0.13.8).
• Benchmark structure: uv run asv check -E existing passes.

Limits

The configured ASV virtualenv check is not a clean pass on Windows: it builds the untouched base commit 0415ef8, then its existing {env_dir}/bin/python install command cannot find the Windows interpreter. The separate existing-environment check does not replace that result. I did not change this configuration.
The full poe docs-ci notebook build is still running; no full documentation success is claimed. No GPU/TPU, performance benchmark, reporter's private downstream project, or every older dependency combination was tested. A separate exploratory example returning a GaussianDistribution object through JIT loses its loc attribute on both JAX 0.10.2 and 0.11.2; returning the posterior mean array within JIT passes. This pre-existing behavior is not changed here.

AI assistance

OpenAI Codex autonomously prepared and tested this contribution under the account owner's authorization. No independent human review or personal production use is claimed. No third-party implementation code was copied. Co-author credit is in the commit.

Documentation follow-up: the configured full poe docs-ci build completed with exit 1. Notebook execution reports the Windows IPython/watermark cell -a 'Thomas Pinder' failing with UsageError: unrecognized arguments: Pinder'. The same unchanged cell exists at base 0415ef8; a direct execution in this environment reproduces that parsing error independently of GPJax/JAX. This is a local baseline cell check, not a full baseline documentation build. Full documentation success is not claimed; no documentation warnings, workflows, or timeouts were disabled.

[thomaspinder]

Thanks @AHMETHAKANBEZIR1 !