Fix non-euclidean distance metrics + more optimizer rules

Fix so that we actually use distance metrics that match the semantics provided by usearch. Eg. array_cosine_distance and array_negative_inner_product.
Rewrite 1-cosine_similarity to cosine_distance
Optimize min_by(col, arg, k) aggregates if there are indexes
Use proper expression matcher, make index scan binding more accurate in case there are multiple indexes on the same table.
Fix misc bugs
Add more tests

duckdb / duckdb_vss