Phase 0: Project setup for agent-driven development

- Phaser 3 + bitECS 0.4 + TypeScript + Vite stack
- BootScene with title screen
- 6 cursor rules (project context, agent workflow, ECS, chemistry, Phaser, data)
- Vitest configured with happy-dom
- GDD, engine analysis, implementation plan, progress tracking

Co-authored-by: Cursor <cursoragent@cursor.com>

vite.config.ts

@@ -0,0 +1,23 @@
+/// <reference types="vitest" />
+import { defineConfig } from 'vite';
+
+export default defineConfig({
+  base: './',
+  build: {
+    target: 'esnext',
+    rollupOptions: {
+      output: {
+        manualChunks: {
+          phaser: ['phaser'],
+        },
+      },
+    },
+  },
+  server: {
+    port: 5173,
+    open: false,
+  },
+  test: {
+    environment: 'happy-dom',
+  },
+});