s/Operator/Name

[toku-sa-n]

Description of the PR

"Operator" was too specific and did not accurately represent non-operator identifiers such as function and variable names. "Name" is more versatile and appropriately covers both operators and identifiers.

Checklist

• [x] Add a changelog if necessary. See https://keepachangelog.com/ for how to write it.
• [x] Add tests in TESTS.md if possible.