Update gRPC-web generated files

Summary:
Updated gRPC-web code generated files.

Notable changes:

• Using snake_case in proto finally generated proper camelCase here 🎉
• In D10429 I renamed pre_key -> prekey and PreKey -> Prekey - lots of changes here related to this
• Left inline comments for other changes

Original TypeScript generated files: https://gist.github.com/barthap/8e92ae580ddc7ba08a45522e46a04eca

Depends on D10430

Test Plan: yarn flow on web, similiar to D10064 (previous update).

Reviewers: ashoat, varun

Reviewed By: ashoat, varun

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D10573