actions: factor out target parsing
state.rs: rustfmt (mostly)
dbus: use thread channels rather than futures ones
this avoids try_send panicking if the notif-fwd thread cannot keep up with a dbus thread
this could happen at system startup if many messages became available from ModemManager at once
fix compilation around vgtk event handlers
I'm not sure why this stopped working but we now need spaces around the assignment of event handlers in the gtk! macro
hash attachments when creating from path
try to hash attachments when loading db
improve Attachment.ensure_hash interface
use attachment hash in temp filename
avoid errors creating tables and report any encountered errors
note required attachment workaround
add Attachment.sha256 field
tweak Display impl for ModemsError
return () from create_tables