Boost: add Speculation Rules module

[donnchawp]

Almost the same code as in #37579 by @haqadn but that PR was closed.

Fixes #

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Testing instructions:

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Code Coverage Summary

1 file is newly checked for coverage.

File	Coverage
projects/plugins/boost/app/modules/optimizations/speculation-rules/Speculation_Rules.php	0/38 (0.00%) 💔

Full summary · PHP report · JS report

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