chore(spawn-local-jdk): prune glob tree walks in JDKHomeBasedPatternDetector

[deer]

The glob expansion in JDKHomeBasedPatternDetector previously matched only the full-path glob once a leaf directory was reached, meaning a tree walk had to descend into every directory under the base path even when an early segment could never match. This pulled the giant inline lambda in expandPattern's stream pipeline out into named static methods (expandPattern, isGlobPattern, expandGlobPattern, indexOfBaseEnd) and added a GlobSegments helper plus a PruningGlobVisitor.

GlobSegments splits a glob suffix into its individual path segments (respecting {...}/[...] groups so a separator nested inside one doesn't get sliced apart) and builds a PathMatcher per fixed-depth segment before the first **, if any. PruningGlobVisitor then checks each directory against its corresponding segment matcher as soon as it's visited and returns SKIP_SUBTREE the moment a segment fails to match, rather than walking the whole subtree first. When a {...}/[...] group spans a path separator, the per-segment assumption breaks down, so the code falls back to unpruned full-glob matching for that pattern, exactly as before.

Behavior is otherwise unchanged: plain paths still resolve to themselves without touching the filesystem, non-existent base paths and invalid patterns still yield an empty stream, and FOLLOW_LINKS plus AccessDeniedException handling during the walk are preserved.