feat(tui): W puts the pane layout back

Hiding panes with w and zooming with z had no way back short of
pressing each hidden pane's number and Esc. W shows every pane and
leaves zoom in one go, and the shortcut bar offers it only while there
is a layout to reset.

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

@@ -1,5 +1,5 @@
 use super::MainTui;
-use crate::models::{CommandBarMode, FocusedPane, LogView};
+use crate::models::{CommandBarMode, FocusedPane, LogView, PaneLayout};
 use crate::ui::page_of;
 use crate::ui::panes::{
     InfoSubject, name_end_offset, query_end_offset, selected_transfer,
@@ -100,6 +100,10 @@ impl MainTui {
                 self.state.hide_focused_pane();
                 return;
             }
+            KeyCode::Char('W') => {
+                self.state.layout = PaneLayout::default();
+                return;
+            }
             KeyCode::Esc if self.state.layout.zoomed => {
                 self.state.layout.zoomed = false;
                 return;