Module vector_btree 

Vector B-tree storage support modules.

• value_codec (slice A) — self-contained LZ4 codec used by the B-tree large-value path to decide whether a payload is worth compressing before considering an overflow spill.
• page_format (slice C) — on-disk page format v2: adds PageType::Overflow, two flag bits on every leaf cell, and a format-version bump with v1 backward-read compatibility.

Subsequent slices will wire these modules into the engine’s overflow chain, page integration, and MVCC glue.

Modules

page_format

Compatibility facade for the vector B-tree persisted page format.

value_codec

Compatibility facade for the vector/B-tree persisted value codec.