Feat v0.6.12 css isolation (#47)

Co-authored-by: Jeffrey Smith <jasafpro@gmail.com>
Co-committed-by: Jeffrey Smith <jasafpro@gmail.com>

packages/icd-test-runner/js/main.js

@@ -24,6 +24,7 @@
 
   var mount = document.getElementById('extension-mount');
   if (!mount) return;
+  mount.classList.add('ext-icd-test-runner-root');
 
   // ─── Boot Preact SDK (v0.37.14) ───────────────────────────
   // Extension surfaces don't load Preact vendors or the SDK.

packages/icd-test-runner/js/tier-sdk.js

@@ -337,7 +337,7 @@
     await T.test('sdk', 'pipe-render', 'Render filter modifies DOM', async function () {
       sw.pipe.render(1, function (ctx) {
         if (ctx.element.dataset.sdkRenderTest) {
-          ctx.element.classList.add('sdk-render-modified');
+          ctx.element.classList.add('ext-icd-test-runner-sdk-render-modified');
         }
         return ctx;
       }, { source: '_test-render-dom' });
@@ -348,7 +348,7 @@
         element: el, message: null,
         channel: { id: 'fake', type: 'direct' }
       });
-      T.assert(el.classList.contains('sdk-render-modified'), 'element should have class');
+      T.assert(el.classList.contains('ext-icd-test-runner-sdk-render-modified'), 'element should have class');
     });
 
     await T.test('sdk', 'pipe-render', 'Priority ordering in render chain', async function () {