Add async-safe polyfills, Jest custom config, and improved token validation

- Introduced Web Crypto API polyfills (`@peculiar/webcrypto`) for Node.js to enable SSR-safe cryptography utilities.
- Added Jest setup file for global mocks (e.g., `localStorage`, `sessionStorage`, and `TextEncoder/Decoder`).
- Enhanced token validation behavior in `storage` tests to reject incomplete tokens.
- Replaced runtime configuration validation with clamping using `parseIntSafe` constraints for improved reliability.
- Updated `package.json` and `package-lock.json` to include new dependencies (`@peculiar/webcrypto` and related libraries).

frontend/package-lock.json

@@ -40,6 +40,7 @@
       "devDependencies": {
         "@eslint/eslintrc": "^3",
         "@hey-api/openapi-ts": "^0.86.11",
+        "@peculiar/webcrypto": "^1.5.0",
         "@playwright/test": "^1.56.1",
         "@tailwindcss/postcss": "^4",
         "@testing-library/jest-dom": "^6.9.1",
@@ -2349,6 +2350,48 @@
         "node": ">=12.4.0"
       }
     },
+    "node_modules/@peculiar/asn1-schema": {
+      "version": "2.5.0",
+      "resolved": "https://registry.npmjs.org/@peculiar/asn1-schema/-/asn1-schema-2.5.0.tgz",
+      "integrity": "sha512-YM/nFfskFJSlHqv59ed6dZlLZqtZQwjRVJ4bBAiWV08Oc+1rSd5lDZcBEx0lGDHfSoH3UziI2pXt2UM33KerPQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "asn1js": "^3.0.6",
+        "pvtsutils": "^1.3.6",
+        "tslib": "^2.8.1"
+      }
+    },
+    "node_modules/@peculiar/json-schema": {
+      "version": "1.1.12",
+      "resolved": "https://registry.npmjs.org/@peculiar/json-schema/-/json-schema-1.1.12.tgz",
+      "integrity": "sha512-coUfuoMeIB7B8/NMekxaDzLhaYmp0HZNPEjYRm9goRou8UZIC3z21s0sL9AWoCw4EG876QyO3kYrc61WNF9B/w==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "^2.0.0"
+      },
+      "engines": {
+        "node": ">=8.0.0"
+      }
+    },
+    "node_modules/@peculiar/webcrypto": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/@peculiar/webcrypto/-/webcrypto-1.5.0.tgz",
+      "integrity": "sha512-BRs5XUAwiyCDQMsVA9IDvDa7UBR9gAvPHgugOeGng3YN6vJ9JYonyDc0lNczErgtCWtucjR5N7VtaonboD/ezg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@peculiar/asn1-schema": "^2.3.8",
+        "@peculiar/json-schema": "^1.1.12",
+        "pvtsutils": "^1.3.5",
+        "tslib": "^2.6.2",
+        "webcrypto-core": "^1.8.0"
+      },
+      "engines": {
+        "node": ">=10.12.0"
+      }
+    },
     "node_modules/@pkgjs/parseargs": {
       "version": "0.11.0",
       "resolved": "https://registry.npmjs.org/@pkgjs/parseargs/-/parseargs-0.11.0.tgz",
@@ -4865,6 +4908,21 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/asn1js": {
+      "version": "3.0.6",
+      "resolved": "https://registry.npmjs.org/asn1js/-/asn1js-3.0.6.tgz",
+      "integrity": "sha512-UOCGPYbl0tv8+006qks/dTgV9ajs97X2p0FAbyS2iyCRrmLSRolDaHdp+v/CLgnzHc3fVB+CwYiUmei7ndFcgA==",
+      "dev": true,
+      "license": "BSD-3-Clause",
+      "dependencies": {
+        "pvtsutils": "^1.3.6",
+        "pvutils": "^1.1.3",
+        "tslib": "^2.8.1"
+      },
+      "engines": {
+        "node": ">=12.0.0"
+      }
+    },
     "node_modules/ast-types-flow": {
       "version": "0.0.8",
       "resolved": "https://registry.npmjs.org/ast-types-flow/-/ast-types-flow-0.0.8.tgz",
@@ -10823,6 +10881,26 @@
       ],
       "license": "MIT"
     },
+    "node_modules/pvtsutils": {
+      "version": "1.3.6",
+      "resolved": "https://registry.npmjs.org/pvtsutils/-/pvtsutils-1.3.6.tgz",
+      "integrity": "sha512-PLgQXQ6H2FWCaeRak8vvk1GW462lMxB5s3Jm673N82zI4vqtVUPuZdffdZbPDFRoU8kAhItWFtPCWiPpp4/EDg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "^2.8.1"
+      }
+    },
+    "node_modules/pvutils": {
+      "version": "1.1.5",
+      "resolved": "https://registry.npmjs.org/pvutils/-/pvutils-1.1.5.tgz",
+      "integrity": "sha512-KTqnxsgGiQ6ZAzZCVlJH5eOjSnvlyEgx1m8bkRJfOhmGRqfo5KLvmAlACQkrjEtOQ4B7wF9TdSLIs9O90MX9xA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=16.0.0"
+      }
+    },
     "node_modules/queue-microtask": {
       "version": "1.2.3",
       "resolved": "https://registry.npmjs.org/queue-microtask/-/queue-microtask-1.2.3.tgz",
@@ -12589,6 +12667,20 @@
         "makeerror": "1.0.12"
       }
     },
+    "node_modules/webcrypto-core": {
+      "version": "1.8.1",
+      "resolved": "https://registry.npmjs.org/webcrypto-core/-/webcrypto-core-1.8.1.tgz",
+      "integrity": "sha512-P+x1MvlNCXlKbLSOY4cYrdreqPG5hbzkmawbcXLKN/mf6DZW0SdNNkZ+sjwsqVkI4A4Ko2sPZmkZtCKY58w83A==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@peculiar/asn1-schema": "^2.3.13",
+        "@peculiar/json-schema": "^1.1.12",
+        "asn1js": "^3.0.5",
+        "pvtsutils": "^1.3.5",
+        "tslib": "^2.7.0"
+      }
+    },
     "node_modules/webidl-conversions": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-7.0.0.tgz",