Moved `sdkVersion` and `environmentPrefix` constants to `packages/sdk`

- Many low-level changes to several packages
- All sdk package tests are passing
- All downstream packages are building, with most tests passing
- TS-SDK functionality is a good commit milestone
- Also fixed a Kotlin model generator formatting bug
- Updated documentation and regenerated TS sdk for Looker 7.20 to verify constants refactor
- also fix `yarn register` for new `NodeSettingsIniFile` method signature

Co-authored-by: Joel Dodge <joeldodge@google.com>
Co-authored-by: Joseph Axisa <jax@looker.com>