Replace expect.js with node:assert/strict

expect.js is unmaintained and unnecessary — Node's built-in assert
module covers all our assertion patterns. This also removes expect.js
from package.json dependencies.

Made-with: Cursor

test/package-lock.json

@@ -12,7 +12,6 @@
         "chromedriver": "^146.0.5"
       },
       "devDependencies": {
-        "expect.js": "^0.3.1",
         "mocha": "^11.7.5",
         "selenium-webdriver": "^4.41.0"
       }
@@ -669,12 +668,6 @@
         "node": ">=0.10.0"
       }
     },
-    "node_modules/expect.js": {
-      "version": "0.3.1",
-      "resolved": "https://registry.npmjs.org/expect.js/-/expect.js-0.3.1.tgz",
-      "integrity": "sha1-sKWaDS7/VDdUTr8M6qYBWEHQm1s=",
-      "dev": true
-    },
     "node_modules/extract-zip": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/extract-zip/-/extract-zip-2.0.1.tgz",
@@ -2414,12 +2407,6 @@
       "resolved": "https://registry.npmjs.org/esutils/-/esutils-2.0.3.tgz",
       "integrity": "sha512-kVscqXk4OCp68SZ0dkgEKVi6/8ij300KBWTJq32P/dYeWTSwK41WyTxalN1eRmA5Z9UU/LX9D7FWSmV9SAYx6g=="
     },
-    "expect.js": {
-      "version": "0.3.1",
-      "resolved": "https://registry.npmjs.org/expect.js/-/expect.js-0.3.1.tgz",
-      "integrity": "sha1-sKWaDS7/VDdUTr8M6qYBWEHQm1s=",
-      "dev": true
-    },
     "extract-zip": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/extract-zip/-/extract-zip-2.0.1.tgz",