fix: restore skin controls and desktop portrait compatibility

Respect host root layout, draw the scrim once, discover appearance controls without build hashes, and recover failed portraits independently. Add unit and real-browser regression coverage.

Refs #8, #12, #15, #10, #13. Native Desktop acceptance remains pending; no release.

package-lock.json

@@ -10,6 +10,7 @@
       "devDependencies": {
         "@types/react": "~18.3.1",
         "esbuild": "^0.25.0",
+        "playwright-core": "^1.64.1",
         "vitest": "^4.1.10"
       }
     },
@@ -1330,6 +1331,19 @@
         "url": "https://github.com/sponsors/jonschlinkert"
       }
     },
+    "node_modules/playwright-core": {
+      "version": "1.64.1",
+      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.64.1.tgz",
+      "integrity": "sha512-BC4s8y6SEVA6Q1rSxZTto8hI1KUI3xXlHGZgvGqP4IqPdI/a6FX9H29IDNz7vKo9l21b6LfYosScPL6M3xxyDQ==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "playwright-core": "cli.js"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
     "node_modules/postcss": {
       "version": "8.5.26",
       "resolved": "https://registry.npmmirror.com/postcss/-/postcss-8.5.26.tgz",