Consistent use of terminology for "remotes"

[ntrogh]

We have inconsistencies across docs when referring to a remote window (remote, remote window, remote context, remote machine).

• [ ] Clearly define the terminology in the Remote docs and align all docs accordingly.
• [ ] Review terminology used in the product
• [ ] Include terminology to glossary

Related: https://github.com/microsoft/vscode-docs/pull/7322#discussion_r1618420702