refactor: clear the quality-scan findings

`render_shortcuts` was 144 lines of "which shortcuts apply" wrapped around 40
lines of drawing; the decision moves into a `shortcuts` method beside the
`rooms_shortcuts` helper that already worked this way. Three identically
shaped comments over the popup guards collapse into one that carries the part
worth knowing — an open popup owns the keyboard, so the order matters. The
state tests trade bare `unwrap()` for `expect()` so a failure names the step.

soulseek-rs/src/persist/state.rs

@@ -185,7 +185,7 @@ mod tests {
     use super::*;
 
     fn store() -> (tempfile::TempDir, StateStore) {
-        let dir = tempfile::tempdir().unwrap();
+        let dir = tempfile::tempdir().expect("a temporary state directory");
         let store = StateStore::new(dir.path().join("state"));
         (dir, store)
     }
@@ -254,25 +254,32 @@ mod tests {
     fn corrupt_file_loads_as_empty_and_is_kept_as_bak() {
         let (tmp, store) = store();
         let path = tmp.path().join("state").join("downloads.json");
-        std::fs::create_dir_all(path.parent().unwrap()).unwrap();
-        std::fs::write(&path, "{ not json").unwrap();
+        std::fs::create_dir_all(path.parent().expect("a parent"))
+            .expect("the state directory");
+        std::fs::write(&path, "{ not json").expect("the corrupt file");
         assert_eq!(store.load_downloads(), vec![]);
         // The bad file is set aside, not left to be overwritten.
         assert!(!path.exists());
         let bak = path.with_extension("json.bak");
-        assert_eq!(std::fs::read_to_string(bak).unwrap(), "{ not json");
+        assert_eq!(
+            std::fs::read_to_string(bak).expect("the .bak"),
+            "{ not json"
+        );
     }
 
     #[test]
     fn a_second_corrupt_file_replaces_the_previous_bak() {
         let (tmp, store) = store();
         let path = tmp.path().join("state").join("downloads.json");
-        std::fs::create_dir_all(path.parent().unwrap()).unwrap();
-        std::fs::write(path.with_extension("json.bak"), "old bak").unwrap();
-        std::fs::write(&path, "{ newer corruption").unwrap();
+        std::fs::create_dir_all(path.parent().expect("a parent"))
+            .expect("the state directory");
+        std::fs::write(path.with_extension("json.bak"), "old bak")
+            .expect("the previous .bak");
+        std::fs::write(&path, "{ newer corruption").expect("the corrupt file");
         assert_eq!(store.load_downloads(), vec![]);
         assert_eq!(
-            std::fs::read_to_string(path.with_extension("json.bak")).unwrap(),
+            std::fs::read_to_string(path.with_extension("json.bak"))
+                .expect("the .bak"),
             "{ newer corruption"
         );
     }
@@ -281,8 +288,10 @@ mod tests {
     fn file_from_a_newer_build_loads_as_empty_and_is_kept_as_bak() {
         let (tmp, store) = store();
         let path = tmp.path().join("state").join("rooms.json");
-        std::fs::create_dir_all(path.parent().unwrap()).unwrap();
-        std::fs::write(&path, r#"{"version": 99, "data": ["x"]}"#).unwrap();
+        std::fs::create_dir_all(path.parent().expect("a parent"))
+            .expect("the state directory");
+        std::fs::write(&path, r#"{"version": 99, "data": ["x"]}"#)
+            .expect("the newer-version file");
         assert_eq!(store.load_rooms(), Vec::<String>::new());
         assert!(!path.exists());
         assert!(path.with_extension("json.bak").exists());

soulseek-rs/src/ui/main_tui/input.rs

@@ -16,17 +16,13 @@ impl MainTui {
             return self.handle_chat_input(key);
         }
 
-        // Browse popup takes over navigation while open.
+        // An open popup owns the keyboard, so these come before pane routing.
         if self.state.show_browse {
             return self.handle_browse_input(key);
         }
-
-        // Rooms popup takes over navigation while open.
         if self.state.show_rooms {
             return self.handle_rooms_input(key);
         }
-
-        // Settings popup takes over navigation while open.
         if self.state.settings.is_some() {
             return self.handle_settings_input(key);
         }
@@ -149,7 +145,6 @@ impl MainTui {
             KeyCode::BackTab | KeyCode::Up | KeyCode::Char('k') => {
                 self.state.cycle_chat_peer(false);
             }
-            // Start a conversation with someone not in the list yet.
             KeyCode::Char('m') => {
                 self.state.show_messages = false;
                 self.state.command_bar_active = true;

soulseek-rs/src/ui/main_tui/render.rs

@@ -298,8 +298,10 @@ impl MainTui {
         }
     }
 
-    fn render_shortcuts(&self, frame: &mut Frame, area: Rect) {
-        let shortcuts = if self.state.settings.is_some() {
+    /// Which shortcuts the bar offers, which is purely a question of what is
+    /// open and where the focus sits. Sibling of [`Self::rooms_shortcuts`].
+    fn shortcuts(&self) -> Vec<(&'static str, &'static str)> {
+        if self.state.settings.is_some() {
             vec![
                 ("↑↓", "move"),
                 ("Enter/e", "edit download dir"),
@@ -399,9 +401,11 @@ impl MainTui {
                     ]
                 }
             }
-        };
+        }
+    }
 
-        let shortcuts_line = format_shortcuts_styled(&shortcuts);
+    fn render_shortcuts(&self, frame: &mut Frame, area: Rect) {
+        let shortcuts_line = format_shortcuts_styled(&self.shortcuts());
         // Surface our own sharing status in the block title.
         let shared = self.client.shared_directories();
         let sharing = match shared.as_slice() {