v0.1.3 — Clearer package docs and Metal transpose fix

The PyPI description now has a short overview, platform requirements, installation commands and a runnable Python example. Detailed API contracts and numerical references moved to docs/technical.md, and package metadata now links to the repository, documentation and issue tracker.

pip install medmlx-core==0.1.3

This release also contains the previously merged Metal fix for lazy stride-2 transpose-convolution outputs. See the decoder note for its scope and independent reproducer. The documentation changes add no runtime changes beyond the existing main branch.

Validation: 220 tests passed against the installed wheel on macOS arm64 / Python 3.12 / MLX 0.32.3 Metal; the README example ran successfully; wheel and source metadata passed twine check; publication scanning found no blockers or warnings.

Static checks retain the existing backlog of 151 Ruff findings and 719 Pyright errors. They are not claimed clean. Apache-2.0 licensing and upstream notices are retained.