feat(core): initialize project skeleton with Electron + React + TypeScript

Set up the complete project foundation for ClawX, a graphical AI assistant:

- Electron main process with IPC handlers, menu, tray, and gateway management
- React renderer with routing, layout components, and page scaffolding
- Zustand state management for gateway, settings, channels, skills, chat, and cron
- shadcn/ui components with Tailwind CSS and CSS variable theming
- Build tooling with Vite, electron-builder, and TypeScript configuration
- Testing setup with Vitest and Playwright
- Development configurations (ESLint, Prettier, gitignore, env example)

electron/main/window.ts

@@ -0,0 +1,84 @@
+/**
+ * Window Management Utilities
+ * Handles window state persistence and multi-window management
+ */
+import { BrowserWindow, screen } from 'electron';
+import Store from 'electron-store';
+
+interface WindowState {
+  x?: number;
+  y?: number;
+  width: number;
+  height: number;
+  isMaximized: boolean;
+}
+
+const store = new Store<{ windowState: WindowState }>({
+  name: 'window-state',
+  defaults: {
+    windowState: {
+      width: 1280,
+      height: 800,
+      isMaximized: false,
+    },
+  },
+});
+
+/**
+ * Get saved window state with bounds validation
+ */
+export function getWindowState(): WindowState {
+  const state = store.get('windowState');
+  
+  // Validate that the window is visible on a screen
+  if (state.x !== undefined && state.y !== undefined) {
+    const displays = screen.getAllDisplays();
+    const isVisible = displays.some((display) => {
+      const { x, y, width, height } = display.bounds;
+      return (
+        state.x! >= x &&
+        state.x! < x + width &&
+        state.y! >= y &&
+        state.y! < y + height
+      );
+    });
+    
+    if (!isVisible) {
+      // Reset position if not visible
+      delete state.x;
+      delete state.y;
+    }
+  }
+  
+  return state;
+}
+
+/**
+ * Save window state
+ */
+export function saveWindowState(win: BrowserWindow): void {
+  const isMaximized = win.isMaximized();
+  
+  if (!isMaximized) {
+    const bounds = win.getBounds();
+    store.set('windowState', {
+      x: bounds.x,
+      y: bounds.y,
+      width: bounds.width,
+      height: bounds.height,
+      isMaximized,
+    });
+  } else {
+    store.set('windowState.isMaximized', true);
+  }
+}
+
+/**
+ * Track window state changes
+ */
+export function trackWindowState(win: BrowserWindow): void {
+  // Save state on window events
+  ['resize', 'move', 'close'].forEach((event) => {
+    win.on(event as any, () => saveWindowState(win));
+  });
+}