fix: preserve type-only baseline declarations safely

.gitattributes

@@ -0,0 +1 @@
+fixtures/typescript/tests/baselines/reference/* -text whitespace=cr-at-eol

README.md

@@ -1,6 +1,6 @@
 # TypeScript Baseline Lib Generator
 
-Generates `baseline.d.ts`, a TypeScript lib that contains only the JavaScript built-ins that are [Baseline widely available](https://web.dev/baseline). It classifies the `javascript.builtins.*` compat rows from `web-features` and emits the declarations whose `baselineStatus` is `"high"`.
+Generates `baseline.d.ts`, a TypeScript lib for TypeScript-declarable JavaScript features that are [Baseline widely available](https://web.dev/baseline). It currently classifies `javascript.builtins.*` and the `arguments` object from `web-features`.
 
 ## Using the lib
 
@@ -14,18 +14,17 @@ npm install --save-dev typescript-baseline-lib
 {
   "compilerOptions": {
     "noLib": true,
-    "skipLibCheck": true,
     "types": ["typescript-baseline-lib"]
   }
 }
 ```
 
-Now only Baseline widely available built-ins type-check. APIs that haven't reached Baseline yet (`Promise.withResolvers`, `Array.fromAsync` until it promotes, and so on) are reported as errors. The end goal is first-class `--lib baseline` support upstream in TypeScript.
+Now only the supported Baseline widely available JavaScript surfaces type-check. APIs that haven't reached Baseline yet (`Promise.withResolvers`, `Array.fromAsync` until it promotes, and so on) are reported as errors. The end goal is first-class `--lib baseline` support upstream in TypeScript.
 
 ## Current contract
 
 - Target is `baseline` only.
-- Scope is `javascript.builtins.*` only.
+- Scope is TypeScript-declarable JavaScript surfaces: `javascript.builtins.*` plus the `arguments` object.
 - DOM, Web Worker, syntax, grammar, statements, and operators are out of scope.
 - Special compat rows are managed in `registry/compat-management.json` with a source URL for each.
-- The checked-in dataset, derived, and generated artifacts are overwritten with the rolling latest; history lives in Git.
+- The checked-in dataset, derived, and generated artifacts are overwritten with the rolling latest; history lives in Git.

deploy/package-registry.mjs

@@ -11,7 +11,7 @@ export const deployGeneratedDirectory = path.join(deployDirectory, "generated");
 export const baselinePackage = {
     id: "baseline",
     name: "typescript-baseline-lib",
-    description: "Baseline widely available JavaScript built-in declarations for TypeScript.",
+    description: "Baseline widely available JavaScript declarations for TypeScript.",
     initialVersion: "0.0.1",
     license: "Apache-2.0",
     keywords: [

deploy/readmes/baseline.md

@@ -2,7 +2,7 @@
 
 Generated `baseline` declarations for TypeScript.
 
-This package is produced by the [`TypeScript-Baseline-lib-generator`](https://github.com/3ru/TypeScript-Baseline-lib-generator) repo. It packages the JavaScript built-ins that are [Baseline widely available](https://web.dev/baseline) (`baselineStatus === "high"`) as a single global declaration bundle.
+This package is produced by the [`TypeScript-Baseline-lib-generator`](https://github.com/3ru/TypeScript-Baseline-lib-generator) repo. It packages TypeScript-declarable JavaScript features that are [Baseline widely available](https://web.dev/baseline) as a single global declaration bundle.
 
 Current snapshot:
 
@@ -26,16 +26,15 @@ npm install --save-dev {{PACKAGE_NAME}}
 {
   "compilerOptions": {
     "noLib": true,
-    "skipLibCheck": true,
     "types": ["{{PACKAGE_NAME}}"]
   }
 }
 ```
 
-Now only Baseline widely available built-ins type-check; APIs that haven't reached Baseline yet are reported as errors.
+Now only the supported Baseline widely available JavaScript surfaces type-check; APIs that haven't reached Baseline yet are reported as errors.
 
 ## Notes
 
 - The public surface is a single `baseline` lib.
-- The current scope is `javascript.builtins.*` only.
+- The current scope is `javascript.builtins.*` plus the `arguments` object.
 - The generated declarations are derived from the npm `typescript` package and preserve the upstream Microsoft license notice inside `baseline.d.ts`.