Array-api Linalg functions

It might be nice to add the following functions to blosc2, which are included in the linalg module of the array-api standard. See src/blosc2/linalg.py for function signatures.

- [ ] array_api_tests/test_linalg.py::test_cholesky
- [ ] array_api_tests/test_linalg.py::test_cross
- [ ] array_api_tests/test_linalg.py::test_det
- [ ] array_api_tests/test_linalg.py::test_diagonal
- [ ] array_api_tests/test_linalg.py::test_eigh
- [ ] array_api_tests/test_linalg.py::test_eigvalsh
- [ ] array_api_tests/test_linalg.py::test_inv
- [ ] array_api_tests/test_linalg.py::test_linalg_matmul - add @ operator
- [x] ~array_api_tests/test_linalg.py::test_matmul~
- [ ] array_api_tests/test_linalg.py::test_matrix_norm
- [ ] array_api_tests/test_linalg.py::test_matrix_power
- [ ] array_api_tests/test_linalg.py::test_matrix_rank
- [ ] array_api_tests/test_linalg.py::test_linalg_matrix_transpose
- [x] ~array_api_tests/test_linalg.py::test_matrix_transpose~
- [x] array_api_tests/test_linalg.py::test_outer (but this can be optimised since chunks don't need to be decompressed)
- [ ] array_api_tests/test_linalg.py::test_pinv
- [ ] array_api_tests/test_linalg.py::test_qr
- [ ] array_api_tests/test_linalg.py::test_slogdet
- [ ] array_api_tests/test_linalg.py::test_solve
- [ ] array_api_tests/test_linalg.py::test_svd
- [ ] array_api_tests/test_linalg.py::test_svdvals
- [ ] array_api_tests/test_linalg.py::test_linalg_tensordot
- [x] ~array_api_tests/test_linalg.py::test_tensordot~
- [ ] array_api_tests/test_linalg.py::test_trace
- [ ] array_api_tests/test_linalg.py::test_linalg_vecdot
- [x] ~array_api_tests/test_linalg.py::test_vecdot~
- [ ] array_api_tests/test_linalg.py::test_vecdot_conj
- [ ] array_api_tests/test_linalg.py::test_vector_norm