v0.9.0dev: dev. release for public testing (mostly typing changes)

What's Changed

• upgrade python versions, stop using/supporting python 3.9, set version to 0.9.0dev by @arogozhnikov in #396
• use list/dict/tuple instead of List/Dict/Tuple by @arogozhnikov in #397
• typing.Sequence -> collections.abc.Sequence + switch off a couple of ruff rules by @arogozhnikov in #398
• add einops playground by @arogozhnikov in #400
• MLXBackend: Rename add_axes method to add_axis by @Datamance in #401
• framework name: mlx -> mlx.core by @arogozhnikov in #403
• fix the einops.ReductionCallable type by @jorenham in #405
• modernize annotations with PEP 604 union syntax by @jorenham in #410
• explicitly mark type aliases as TypeAlias (PEP 613) by @jorenham in #411
• Add ruff rules, set correct requires-version, update ruff by @arogozhnikov in #412
• proper typing of array_api submodule by @arogozhnikov in #413
• remove unnecessary overloads by @arogozhnikov in #414
• fix mypy errors in einops.parsing and add missing annotations by @jorenham in #417
• fill in the missing annotations in einops.layers.oneflow by @jorenham in #421
• fix mypy errors in einops.layers.paddle and add missing annotations by @jorenham in #422
• fix mypy errors in einops.layers.flax and add missing annotations by @jorenham in #420
• fix mypy errors in einops.layers.torch and add missing annotations by @jorenham in #425
• annotate the return type of array_api.asnumpy by @jorenham in #418
• fix mypy errors in einops.layers.__init__ and add missing annotations by @jorenham in #419
• add hatch run check by @arogozhnikov in #426
• minor: remove unused function, adjust test by @arogozhnikov in #427
• suppress/fix various mypy complains by @arogozhnikov in #428
• delete fake setup.py by @arogozhnikov in #429
• more typing work by @arogozhnikov in #430
• resolve rest of mypy complains by @arogozhnikov in #432
• create empty env "pypi" by @arogozhnikov in #437
• switch deployment to uv from hatch by @arogozhnikov in #438

New Contributors

• @Datamance made their first contribution in #401
• @jorenham made their first contribution in #405

Full Changelog: v0.8.2...v0.9.0dev