Fix Shorts support and add userscript voting

Harden Shorts controls, reaction state, and navigation; share voting logic
with the extension; improve ratio-bar rendering; and add comprehensive Jest,
Playwright, artifact, and live-browser regression coverage.

package-lock.json

@@ -18,6 +18,7 @@
         "@babel/core": "^7.23.5",
         "@babel/preset-env": "^7.23.5",
         "@babel/runtime": "^7.23.5",
+        "@playwright/test": "1.62.0",
         "babel-loader": "^10.0.0",
         "babel-plugin-rewire": "^1.2.0",
         "copy-webpack-plugin": "^11.0.0",
@@ -91,6 +92,7 @@
       "version": "7.23.5",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@ampproject/remapping": "^2.2.0",
         "@babel/code-frame": "^7.23.5",
@@ -1740,6 +1742,7 @@
         }
       ],
       "license": "MIT",
+      "peer": true,
       "engines": {
         "node": ">=18"
       },
@@ -1763,6 +1766,7 @@
         }
       ],
       "license": "MIT",
+      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -2537,6 +2541,22 @@
         "node": ">=14"
       }
     },
+    "node_modules/@playwright/test": {
+      "version": "1.62.0",
+      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.62.0.tgz",
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+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "playwright": "1.62.0"
+      },
+      "bin": {
+        "playwright": "cli.js"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
     "node_modules/@sinclair/typebox": {
       "version": "0.24.51",
       "dev": true,
@@ -2974,6 +2994,7 @@
       "version": "8.11.2",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "bin": {
         "acorn": "bin/acorn"
       },
@@ -3003,6 +3024,7 @@
       "version": "6.12.6",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "fast-deep-equal": "^3.1.1",
         "fast-json-stable-stringify": "^2.0.0",
@@ -3504,6 +3526,7 @@
         }
       ],
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "caniuse-lite": "^1.0.30001565",
         "electron-to-chromium": "^1.4.601",
@@ -4515,6 +4538,21 @@
       "dev": true,
       "license": "ISC"
     },
+    "node_modules/fsevents": {
+      "version": "2.3.3",
+      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.3.tgz",
+      "integrity": "sha512-5xoDfX+fL7faATnagmWPpbFtwh/R77WmMMqqHGS65C3vvB0YHrgF+B1YmZ3441tMj5n63k0212XNoJwzlhffQw==",
+      "dev": true,
+      "hasInstallScript": true,
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "darwin"
+      ],
+      "engines": {
+        "node": "^8.16.0 || ^10.6.0 || >=11.0.0"
+      }
+    },
     "node_modules/function-bind": {
       "version": "1.1.1",
       "dev": true,
@@ -5912,6 +5950,7 @@
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       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "cssstyle": "^4.2.1",
         "data-urls": "^5.0.0",
@@ -6644,6 +6683,53 @@
         "node": ">=8"
       }
     },
+    "node_modules/playwright": {
+      "version": "1.62.0",
+      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.62.0.tgz",
+      "integrity": "sha512-Z14dG305dgaLu6foB1TXQagFiW8JfSUIUaUuPaKQ6NtBPKF1P/qXcqfh6c6K/icPqdy37JmjbiBXf6JNg6Sylw==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "playwright-core": "1.62.0"
+      },
+      "bin": {
+        "playwright": "cli.js"
+      },
+      "engines": {
+        "node": ">=20"
+      },
+      "optionalDependencies": {
+        "fsevents": "2.3.2"
+      }
+    },
+    "node_modules/playwright-core": {
+      "version": "1.62.0",
+      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.62.0.tgz",
+      "integrity": "sha512-nsNRyq0r2zsG8AcRHWknc9QRA5XCueC7gWMrs+Gx2tlZn9hcl8zudfh00lhJPY1DE7NmZ6bDsT9g2yey8mXljA==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "playwright-core": "cli.js"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
+    "node_modules/playwright/node_modules/fsevents": {
+      "version": "2.3.2",
+      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.2.tgz",
+      "integrity": "sha512-xiqMQR4xAeHTuB9uWm+fFRcIOgKBMiOBP+eXiyT7jsgVCq1bkVygt00oASowB7EdtpOHaaPgKt812P9ab+DDKA==",
+      "dev": true,
+      "hasInstallScript": true,
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "darwin"
+      ],
+      "engines": {
+        "node": "^8.16.0 || ^10.6.0 || >=11.0.0"
+      }
+    },
     "node_modules/prettier": {
       "version": "3.3.2",
       "dev": true,
@@ -7080,6 +7166,7 @@
       "version": "8.12.0",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "fast-deep-equal": "^3.1.1",
         "json-schema-traverse": "^1.0.0",
@@ -7872,6 +7959,7 @@
       "version": "5.89.0",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@types/eslint-scope": "^3.7.3",
         "@types/estree": "^1.0.0",
@@ -7920,6 +8008,7 @@
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       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@discoveryjs/json-ext": "^0.6.1",
         "@webpack-cli/configtest": "^3.0.1",