Settings: db-viewer redesign, theme/accent wiring, macOS overlay titlebar (#6)

* feat: settings back button returns to origin view (push/pop nav)

* feat: redesign settings screen with db-viewer border styling

* fix: settings sidebar — icon+text tabs, back at top, top border (PR feedback)

* fix: tighten settings sidebar — back and tabs in one group

* fix: settings header shows active tab name instead of duplicated title

* fix: settings — accent back button, header shows active tab; fix App test

* fix: tags settings — no create label, no card chrome (bg/border/padding)

* feat: drag-and-drop tag reordering in settings tags tab

* fix: general settings — remove section card chrome (bg/border/padding)

* fix: merge Appearance and Interface into one settings section

* fix: remove row separators between settings items within sections

* fix: settings rows use gap spacing instead of per-row padding

* feat: strip section cards from all settings tabs; delete SettingsSection

* feat: apply theme and font size settings (appearance wiring)

* feat: honor default folder setting on startup

* feat: confirm_before_delete setting now skips delete confirmations

* feat: default_ports setting prefills new connection forms

* fix: light theme — text colors, native window chrome, ThemePicker preview

* fix: sync window background color with theme so title bar follows light mode

* fix: window-sync test uses microtask flush instead of vi.waitFor

* fix: app root carries canvas bg so home-screen parent matches theme

* fix: grant window set-theme/set-background-color permissions so title bar follows theme

* fix: overlay title bar — webview paints under traffic lights, flat canvas color in both themes

* fix: compact 28px overlay titlebar with visible bottom border

* fix: in-flow titlebar strip (draggable via allowed permission); screens fill remaining height, no bottom clipping

* fix: top border only on settings + db viewer pages, not the titlebar strip

* fix: db viewer sidebar h-screen -> h-full (28px overflow clipped bottom icons)

* fix: system theme resets window to OS before reading matchMedia (was polluted by forced window theme)

* fix: theme switcher labels moved below previews for readability

* feat: configurable accent color setting (circle palette in Appearance)

* docs: update AGENTS.md + README for settings redesign, wired settings, accent color

src-tauri/src/commands/settings.rs

@@ -39,6 +39,7 @@ mod tests {
         let s = get_settings_inner(&st).unwrap();
         assert_eq!(s.theme, "system");
         assert_eq!(s.font_size, "medium");
+        assert_eq!(s.accent_color, "#2563EB");
     }
 
     #[test]
@@ -47,4 +48,11 @@ mod tests {
         update_setting_inner(&st, "theme", "light").unwrap();
         assert_eq!(get_settings_inner(&st).unwrap().theme, "light");
     }
+
+    #[test]
+    fn update_accent_color_persists() {
+        let st = state();
+        update_setting_inner(&st, "accent_color", "#EF4444").unwrap();
+        assert_eq!(get_settings_inner(&st).unwrap().accent_color, "#EF4444");
+    }
 }