Fixes #14072, alternative of #15207

:has() was matching only against descendants or siblings, but not sibling's descendants.

In this variant, I made apply_selector and related functions bidirectional. So the same logic can be applied to all selectors. Changing the direction for selectors passed into :has() broke p:has(+ y) for the test has-with-render-tag and to fix it I added diving into the @render() tags during gathering siblings, which fixed the render-tag-loop test.

I also tried to cache the function retrieving neighbor elements and got the following cache hits rates on the test cases: descendant_forward: 94,23% descendant_backward: 55,91% children_forward: 84,00% children_backward: 33,51% sibling_forward: 69,42% sibling_backward: 59,94% next_forward: 41,40% next_backward: 2,44% Though, I'm not sure how to measure performance change.

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