terminal: Set `TERM_PROGRAM` and `TERM_PROGRAM_VERSION` environment variables in integrated terminal (#14213)

These two environment variables are essential when people need to detect
terminal type and do something. Many popular terminals set them.
fixes https://github.com/zed-industries/zed/issues/4571
Release Notes:
- Set `TERM_PROGRAM` and `TERM_PROGRAM_VERSION` environment variables in
the integrated terminal
([#4571](https://github.com/zed-industries/zed/issues/4571)).
d49727ff10Donough Liu committed on 7/11/2024, 5:48:46 PM· committed by GitHubparentc195c4d