When top-level AND conjuncts pin the query to a single root
(driveId/RootID restrictions), only that space's index is asked; the
restriction itself stays in the query, so this is purely an
optimization. Conservative by design: any top-level OR, negated or
group-nested restriction leaves the fan-out untouched, searching a
space too many is wasted work while skipping one would be wrong.
Mountpoints are kept for result path mapping.
Costs one extra parse of the query in the service; parsing once and
handing the AST to the engines (which currently re-parse per space) is
a follow-up that changes the engine interface.
Dominik Schmidt
95f175fe10