Set sidebar and bottom panel collapsed by default on load

Changes initial state to provide a clean, minimal workspace on page load.
Both sidebar and bottom panel now start collapsed, showing only the editor
area with the empty state message.

Changes:
- Set sidebarCollapsed initial state to true (was false)
- Set bottomPanelCollapsed initial state to true (was false)
- Users can still open panels using toggle buttons in topbar
- Provides cleaner, more focused initial experience
- Editor area shows "No Instrument Selected" empty state on load

Users can easily open the sidebar or bottom panel at any time using the
panel toggle controls in the top-right of the topbar.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: MarkoVcode

benchmesh-serial-service/frontend/src/ui/workbench/WorkbenchLayout.tsx

@@ -63,8 +63,8 @@ export const WorkbenchLayout: React.FC<WorkbenchLayoutProps> = ({
   onSwitchToClassic,
   isElectron
 }) => {
-  const [sidebarCollapsed, setSidebarCollapsed] = useState(false);
-  const [bottomPanelCollapsed, setBottomPanelCollapsed] = useState(false);
+  const [sidebarCollapsed, setSidebarCollapsed] = useState(true);
+  const [bottomPanelCollapsed, setBottomPanelCollapsed] = useState(true);
   const [rightPanelCollapsed, setRightPanelCollapsed] = useState(true); // Right panel not yet implemented
   const [activeView, setActiveView] = useState<ViewType>('instruments');
   const [activeInstruments, setActiveInstruments] = useState<string[]>([]);