Module spatial_segment_ext 

SpatialSegmentExt — pagedb segment operations for R-tree checkpoint data.

The StorageEngine trait handles sparse, sorted, key-value state. For R-tree checkpoint blobs (one per (collection, field) pair, potentially large, sequentially read on cold-open restore) pagedb segments are the appropriate backing. A single segment per (collection, field) reduces B+ tree pressure from O(rtree_node_count) entries to O(1) per index.

The following keys remain on the B+ tree (Namespace::Spatial):

• spatial:_collections — Vec<(String, String)> catalog (collection, field)
• spatial:_next_id — u64 next entry ID
• spatial:{collection}:{field}:docmap — doc_id → entry_id mapping

Only the spatial:{collection}:{field}:rtree blob (CRC32C-wrapped R-tree checkpoint bytes) moves to pagedb segments.

Only compiled on non-WASM targets. WASM stays on the KV blob path.

Traits

SpatialSegmentExt

Extension trait: write, open, and delete R-tree checkpoint segments backed by pagedb encrypted segment files.