docs(simd): tier debt audit + 4-phase integration plan #392

Job	Run time
nostd/thumbv6m-none-eabi/stable	26s
Pass MSRV values to other jobs	3s
tier4-avx512-check	28s
clippy/1.95.0	41s
format/stable	20s
hpc-stream-parallel/rayon	1m 22s
native-backend/stable	8m 28s
cargo-careful	0s
miri	0s
docs/nightly	0s
nightly-simd-polyfill	0s
cross_test/${{ matrix.target }}/${{ matrix.rust }}	0s
blas-msrv	48s
tests/stable	10m 44s
tests/1.95.0	11m 22s
tests/beta	10m 48s
conclusion	0s
	45m 30s

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