releaseFeatureReadResources

Drop all pooled read indices for a handle being closed (else the static pool pins the closed GeoPackage + its DAOs across open/close cycles). Called from GeoPackage.shutdown.

Release any per-handle feature-read resources cached by the platform read path (e.g. the Android per-table FeatureTableIndex cache) so a closed handle isn't pinned. Called from GeoPackage.shutdown.

No-op on JVM: the read path uses the OGC RTree extension per query and caches nothing per handle.