This patch removes the dependence of vector search module
on the cql3 module by moving the contents of cql3/type_json.hh
to types/json_utils.hh and removing the usage of cql3 primary_key
object in vector_store_client. We also make the needed adjustments
to files that were previously using the afformentioned type_json.hh
file.
This fixes the circular dependency cql3 <-> vector_search.
Closesscylladb/scylladb#26482