Remove the SETUP card: the browser tree shows the progress

The setup checklist card (#265), its show_setup view setting, the View
menu checkbox and the preferences file that only remembered it go; the
tree's marks and ghost rows replace them. Session::progress and
model.check's progress stay for agents. An old prefs.json is no longer
read.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

apps/fieldcraft-web/src/web.rs

@@ -188,7 +188,6 @@ fn services(inbox: Inbox, ctx: egui::Context) -> Services {
         pick_save: Some(Box::new(|name: &str, _: &[Filter]| Some(page_path(name)))),
         // The recent list holds the page's files, which go with the page.
         recent_path: None,
-        prefs_path: None,
     }
 }
 

apps/fieldcraft/src/main.rs

@@ -95,7 +95,6 @@ fn services() -> Services {
         })),
         // Beside the recovery folder in the per-user data folder.
         recent_path: fieldcraft_io::recovery::default_dir().and_then(|d| d.parent().map(|p| p.join("recent.json"))),
-        prefs_path: fieldcraft_io::recovery::default_dir().and_then(|d| d.parent().map(|p| p.join("prefs.json"))),
     }
 }