chore: upgrade TypeScript to 6.0.3 and modernize tsconfig

- typescript 5.9.3 to 6.0.3
- moduleResolution Node to bundler (correct for Vite projects)
- target/lib ES2016 to ES2020 (enables flatMap, Promise.allSettled)
- Fix global to globalThis in initMatrix.ts (browser env)
- Fix EventEmitter default to named import in CallControl.ts

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

tsconfig.json

@@ -2,16 +2,16 @@
   "compilerOptions": {
     "sourceMap": true,
     "jsx": "react",
-    "target": "ES2016",
+    "target": "ES2020",
     "module": "ES2020",
     "allowJs": true,
     "strict": true,
     "esModuleInterop": true,
-    "moduleResolution": "Node",
+    "moduleResolution": "bundler",
     "resolveJsonModule": true,
     "outDir": "dist",
     "skipLibCheck": true,
-    "lib": ["ES2016", "DOM"]
+    "lib": ["ES2020", "DOM"]
   },
   "exclude": ["node_modules", "dist"],
   "include": ["src"]