Upgrade TypeScript to ^6.0.3 (#56772)

Summary:
Pull Request resolved: #56772

Upgrades to TypeScript 6.0.3 and updates `typescript-eslint/*` for TS 6.0 compatibility across `react-native` and `metro`.

#### Motivation

TypeScript 6.0 (Mar 2026) will resolve #53565. Before updating in the React Native CLI template, align in RN and Metro source for consistency.

This is an internal change since:
- This upgrade only applies to TS analysis of these repos' source code.
- Edits to `react-native/typescript-config/tsconfig.json` (which *is* distributed) maintain backwards compatibility.

#### Changes

**react-native**

- Bump `typescript` from `^5.8.3` to `^6.0.3`
- Bump `typescript-eslint/*` from `^8.24.0` to `^8.59.2`
- Replace deprecated `moduleResolution: "node"` with `"node16"` and `target: "es5"` with `"es2015"` in codegen-typescript-test
- Add explicit `types: ["jest", "node"]` where needed (TS 6.0 defaults `types` to `[]`)
- Set `strict: false` in configs that only enable specific strict flags (TS 6.0 defaults `strict` to `true`)
- Update `ModuleResolutionKind.NodeJs` to `Node16` in build config

**metro**

- Bump `typescript` from `5.8.3` to `^6.0.3`
- Bump `typescript-eslint/*` from `^8.36.0` to `^8.59.2`
- No tsconfig changes needed (`tsconfig/node20` preset is already TS 6.0 compatible)

Changelog: [Internal]

Reviewed By: christophpurrer

Differential Revision: D104658690

fbshipit-source-id: 9a2feeb257d5783431941a911b17065fcd0389a5

Author: huntie

package.json

@@ -62,7 +62,7 @@
     "@react-native/metro-config": "0.87.0-main",
     "@tsconfig/node22": "22.0.2",
     "@types/react": "^19.1.0",
-    "@typescript-eslint/parser": "^8.36.0",
+    "@typescript-eslint/parser": "^8.59.2",
     "ansi-regex": "^5.0.0",
     "ansi-styles": "^4.2.1",
     "babel-plugin-minify-dead-code-elimination": "^0.5.2",
@@ -116,7 +116,7 @@
     "temp-dir": "^2.0.0",
     "tinybench": "^4.1.0",
     "tinyglobby": "^0.2.15",
-    "typescript": "5.8.3",
+    "typescript": "^6.0.3",
     "ws": "^7.5.10"
   },
   "resolutions": {

packages/eslint-config-react-native/package.json

@@ -27,8 +27,8 @@
     "@babel/core": "^7.25.2",
     "@babel/eslint-parser": "^7.25.1",
     "@react-native/eslint-plugin": "0.87.0-main",
-    "@typescript-eslint/eslint-plugin": "^8.36.0",
-    "@typescript-eslint/parser": "^8.36.0",
+    "@typescript-eslint/eslint-plugin": "^8.59.2",
+    "@typescript-eslint/parser": "^8.59.2",
     "eslint-config-prettier": "^8.5.0",
     "eslint-plugin-eslint-comments": "^3.2.0",
     "eslint-plugin-ft-flow": "^2.0.1",

packages/react-native/tsconfig.json

@@ -1,6 +1,6 @@
 {
   "compilerOptions": {
-    "strictFunctionTypes": false
+    "strict": false
   },
   "include": ["ReactNativeApi.d.ts"]
 }

packages/react-native/types/tsconfig.json

@@ -2,6 +2,7 @@
   "compilerOptions": {
     "module": "commonjs",
     "lib": ["es6"],
+    "strict": false,
     "noImplicitAny": true,
     "noImplicitThis": true,
     "strictFunctionTypes": true,

private/react-native-codegen-typescript-test/tsconfig.json

@@ -3,9 +3,10 @@
     "lib": [
       "es6"
     ],
-    "module": "commonjs",
-    "moduleResolution": "node",
-    "target": "es5",
+    "module": "node16",
+    "moduleResolution": "node16",
+    "target": "es2015",
+    "types": ["jest", "node"],
     "declaration": false,
     "sourceMap": false,
     "outDir": "./lib",

scripts/build/config.js

@@ -98,7 +98,7 @@ function getTypeScriptCompilerOptions(
     case 'node':
       return {
         ...require('@tsconfig/node22/tsconfig.json').compilerOptions,
-        moduleResolution: ModuleResolutionKind.NodeJs,
+        moduleResolution: ModuleResolutionKind.Node16,
       };
   }
 }

scripts/js-api/build-types/templates/tsconfig.test.json

@@ -2,6 +2,7 @@
   "compilerOptions": {
     "module": "esnext",
     "lib": ["es2020"],
+    "strict": false,
     "noImplicitAny": true,
     "noImplicitThis": true,
     "types": [],