Attachment and file downloads always opened the folder the platform
suggests, with no way to change it (#71). The save dialog is built in a
single place, `DocumentDialog::file_dialog`, which never called
`set_directory`.
Settings → General now carries a Download location card to pick a folder
or reset to the platform default. The stored path is resolved when a
download is saved, not when the path is stored: a location can become
unavailable later, such as an unmounted network share, so a download
falls back to the platform default instead of failing.
The setting covers mail attachments and the Files view, which share
`DocumentProvider::export`. Import dialogs keep the platform default,
since a download location does not describe where files are read from.
Tests cover path resolution (empty, missing, a file instead of a
directory, and a usable directory), the dialog built from the setting,
and that settings blobs written before this field still load.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Tomás Romero
neomodeandClaude Opus 5