Files -> Server writes through /api/v2/files/{upload,mkdir,rename} and
DELETE /files (the trash); upload is a Rust command (library_upload) that
picks files in the system dialog and sends them multipart in the field
`files`. A chat's menu opens Tools and skills..., the web's chat-settings
switches over GET/POST /chats/{id}/scope and /allow/clear. A popover can
open at a context menu's point.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
