v0.5.10

Polynomials4ML v0.5.10

Diff since v0.5.9

v0.5.10

• Harden the scalar cubic-spline helpers into a GPU-safe internal API (_spl_grid, _eval_cubic_d): integer truncation uses unsafe_trunc, so the index computation compiles on GPU backends. Downstream packages (e.g. ACEradials) can now build spline layers on these helpers instead of forking the kernel.
• _eval_cubic_d computes the Hermite-cubic value and derivative analytically (no ForwardDiff Dual), with an explicit ForwardDiff correctness test.
• Fix a latent right-endpoint (x = x1) out-of-bounds in the spline evaluation (left-node index clamped to NX-2).
• Wire the previously-orphaned test_splines.jl into the test suite.

Backward-compatible: new internal API + endpoint bugfix.

Merged pull requests:

• Harden scalar cubic-spline helpers as a GPU-safe internal API (#122) (@cortner)