Build a per-anchor Bloom-style filter for :has() argument matching
after an anchor sees a second check for the same traversal scope. The
filter stores salted tag, id, class, and attribute-name hashes from the
child or descendant scope and rejects arguments whose required
identifiers are absent.
This avoids repeatedly walking the same subtree for unrelated :has()
arguments while preserving the single-check case. More complex
direct-child arguments use the descendant scope so hashes from later
descendant compounds cannot cause false rejections.
Keep the filter conservative for quirks-mode class selectors and for
sibling-combinator relative selectors during invalidation metadata
collection. Text tests cover cache-primed misses for both cases.
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