Bump typescript from 5.9.3 to 6.0.3

package.json

@@ -37,7 +37,7 @@
     "jest": "^30.1.3",
     "prettier": "3.8.1",
     "ts-jest": "^29.1.4",
-    "typescript": "~5.9.2",
+    "typescript": "~6.0.3",
     "typescript-eslint": "^8.58.0"
   },
   "homepage": "https://github.com/Azure/openapi-diff",

tsconfig.json

@@ -42,7 +42,9 @@
     // "paths": {},                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
     // "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
     // "typeRoots": [],                       /* List of folders to include type definitions from. */
-    // "types": [],                           /* Type declaration files to be included in compilation. */
+    // TypeScript >= v6 no longer auto-includes @types/* packages from node_modules/@types.
+    // Without this, test files fail with TS2593: "Cannot find name 'test'/'describe'/'it'".
+    "types": ["jest", "node"],                /* Type declaration files to be included in compilation. */
     // "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
     "esModuleInterop": true,                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
     // "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */