While working through the type feedback implementation, I left some
documentation and fixed some oddities or inconsistencies.

R=jkummerow@chromium.org

Bug: v8:13209
Change-Id: I6ba9b77ecf30ae020a57f77435005a1a57c2fc7e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3840293Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82591}