Fix UI padding and text flush against container edges

- Remove global * { padding: 0 } reset that was overriding all Tailwind
  padding classes (unlayered CSS beats Tailwind v4 @layer utilities)
- Add color-scheme: dark to fix native form controls (select dropdowns)
  rendering with white backgrounds
- Make sidebar responsive (25% width, min 224px, max 320px)
- Increase internal padding on TopBar, Sidebar, ProjectList, StatusBar
- Add flex-shrink-0 to TopBar status indicators to prevent clipping
- Allow project action buttons to wrap on narrow sidebars
- Increase terminal view padding for breathing room

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/src/components/terminal/TerminalView.tsx

@@ -170,7 +170,7 @@ export default function TerminalView({ sessionId, active }: Props) {
     <div
       ref={containerRef}
       className={`w-full h-full ${active ? "" : "hidden"}`}
-      style={{ padding: "4px" }}
+      style={{ padding: "8px" }}
     />
   );
 }