Persist settings nav across every settings sub-page

Each ely://settings/* route used to render its content alone, with no
nav column — so clicking a sidebar item replaced the entire page and
read to users as a brand-new tab opening. Move the nav column into a
shared render_settings_shell wrapper and route every settings/* URL
through it. ely://sync/status reuses the sync route highlight.

Also stop in-place navigation from stealing focus to the omnibar so
the destination page keeps focus for scroll and interaction.

crates/ely_app/src/shell/navigation.rs

@@ -58,6 +58,11 @@ impl ElyShell {
     /// Navigate the active tab to `url` without creating a new tab.
     /// Falls back to opening a new tab only if there's no active tab
     /// to navigate (the BrowserCore returns `TabNotFound`).
+    ///
+    /// Note: in-place navigation does NOT steal focus to the omnibar.
+    /// Settings nav clicks, home pills, and disclosure rows expect
+    /// focus to stay on the page so the user can immediately scroll
+    /// or interact with the destination.
     pub(crate) fn navigate_active_tab(
         &mut self,
         url: UrlText,
@@ -69,7 +74,6 @@ impl ElyShell {
                 core.open_tab(url);
             }
             self.sync_address_input(window, cx);
-            self.focus_address_bar(window, cx);
             cx.notify();
         }
     }