Tracing values (#6679)

* Switch to serde_json::Value for Visitor values

* add tests

* switch Visitor to use Map

* refactor change names

* \n

* update integration test

* use discrete maps for each type of recorded value

* update integration test

* add docs

* Update client/tracing/src/lib.rs

Co-authored-by: Kian Paimani <[email protected]>

* add docs

Co-authored-by: Matt Rutherford <[email protected]>
Co-authored-by: Kian Paimani <[email protected]>