[ENH] For local: use subquery for FTS, unions for int & float metadata expr, is true -> is not null (#4556)

## Description of changes

Move FTS to subquery approach for improved performance, and use unions
in the case of int and float metadata, and replace is true uses with is
not null to utilize db indexes
before (0.6.3):

![image](https://github.com/user-attachments/assets/64d84ebe-2d76-40f8-b2a7-d8854e8592ca)

![image](https://github.com/user-attachments/assets/bb6a701e-3fa7-4f47-a639-d156fd1f6f59)

after:

![image](https://github.com/user-attachments/assets/3ecd1826-933c-483e-89d8-46806fd31851)

![image](https://github.com/user-attachments/assets/760932a3-962d-4f24-88e4-5ab2a488db22)


## Test plan

_How are these changes tested?_

- [ ] Tests pass locally with `pytest` for python, `yarn test` for js,
`cargo test` for rust

## Documentation Changes

_Are all docstrings for user-facing APIs updated if required? Do we need
to make documentation changes in the [docs
section](https://github.com/chroma-core/chroma/tree/main/docs/docs.trychroma.com)?_

Author: jairad26