[ENH] Update `ef_search` default value to 100

[itaismith]

Description of changes

Update the default value of ef_search to 100. Many users experienced bad recall with large collections, and increasing ef_search generally ameliorates the issue. Example: https://github.com/chroma-core/chroma/issues/1737

Test plan

How are these changes tested?

• [x] Tests pass locally with pytest for python, yarn test for js, cargo test for rust

Documentation Changes

Collection configuration section updated.