fix: force onnxruntime-web@1.18.0 via resolutions to eliminate nested 1.24.3

vad-web's own dependency was resolved to ort@1.24.3 (nested in its
node_modules), which only has threaded WASM requiring a .mjs dynamic
import that Vite fails to serve correctly. Pin ort to 1.18.0 via yarn
resolutions so all packages share the same copy with ort-wasm-simd.wasm
(non-threaded SIMD). Also remove the now-unnecessary COOP/COEP headers.

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

package.json

@@ -138,6 +138,7 @@
     "vitest-axe": "^1.0.0-pre.3"
   },
   "resolutions": {
+    "onnxruntime-web": "1.18.0",
     "@livekit/components-core/rxjs": "^7.8.1",
     "@livekit/track-processors/@mediapipe/tasks-vision": "^0.10.18",
     "minimatch": "^10.2.3",