Function useCorpusEntries

Every entry in the surrounding corpus, with corpus-absolute paths and viewer-supplied hrefs — the surface a content component queries instead of useMetadataQuery, whose keys are filesystem-absolute and therefore carry the mount prefix.

Returns an empty array outside a corpus, so a component written for a corpus renders nothing rather than throwing when someone drops it elsewhere. The array keeps its identity while the store and root are unchanged, so it is safe in dependency arrays.