A zero-norm vector is lawful inside brainy (cosine distance scores it at
maximum, never a false top hit) but a false attractor for a downstream
engine serving squared-euclidean distance, which cannot tell a real
all-zero vector apart from a legitimate origin point.
- The VFS root now persists with vector [] (the existing "unvectored"
shape) instead of a real all-zero 384-dim placeholder, and is never
routed into the deferred-embed pipeline.
- A one-time migration in the root-init path detects a pre-fix store's
all-zero placeholder root (by norm, not length) and rewrites it to []
through a new sanctioned Brainy method that keeps the canonical
vectored-noun ledger honest and removes the row from the vector index.
- The vector-index write seam (AddToVectorIndexOperation,
ReplaceInVectorIndexOperation, and the generation materializer's direct
insert) now refuses any real all-zero vector before it reaches a
provider, loudly naming the entity, while the canonical write still
lands.
- add()'s dimension-pinning and HNSW-insert gates, and the add-params
validator, now treat any empty vector as carrying no dimension
information, closing a latent trap where an explicit `vector: []`
would have pinned dimensions to 0.
