Avoid copy by using VectorView and update benchmark.py for sqlite-vec

[1yefuwang1]

This PR does 3 things:

1. Introduce VectorView to avoid unnecessary copy of vectors
2. Register vector_distance, vector_to_json, vector_from_json as SQLITE_INNOCUOUS and SQLITE_DETERMINISTIC see https://sqlite.org/forum/forumpost/4a8b1f9d3b . So that brute force with vectorlite can be simply done by select rowid from my_table order by vector_distance(some_vector, embedding, 'l2') asc limit 10
3. Update benchmark.py for sqlite-vec

The benchmark data will be updated when I get access to my PC.