- Remove section on "Yes to All" RPC authorization
(and add TODO item for if this feature is reintroduced)
- Replace `$` keywords with `@` in qrexec policy docs
- Incorporate Qubes 4.0 "Extra keywords" material into RPC admin docs
- Move some material to a new section on RPC security concerns
- Moves the "Qubes RPC internals" section to qrexec-internals.md.
- Fixes redirects for new pages.
- Retitles docs to reflect deprecation of qrexec2.
- Revises the texts and links referring to deprecated qrexec2 docs.