update docs

Author: nicholasrice

doc-site/docs/getting-started.md

@@ -61,7 +61,7 @@ const myLibraryConfig: Library.Config<IMyLibrary> = {
     body: {
       type: DesignToken.Type.Typography
       value: {
-        fontFamily: (tokens) => tokens.typography.fonts.base, // Alias
+        fontFamily: Library.derive((tokens) => tokens.typography.fonts.base), // Alias
         fontSize: "14px",
         fontWeight: 400;
         letterSpacing: "0px";
@@ -90,12 +90,12 @@ const config: Library.Config<Colors> = {
   },
   alias: {
     type: DesignToken.Type.Color,
-    value: (tokens) => tokens.static, // alias to the 'static' token
+    value: Library.derive((tokens) => tokens.static), // alias to the 'static' token
   },
   derived: {
     type: DesignToken.Type.Color,
     // Operate on the value of the 'alias' token
-    value: (tokens) => darken(tokens.alias.value, 0.3),
+    value: Library.derive((tokens) => darken(tokens.alias.value, 0.3)),
   },
 };
 ```
@@ -149,7 +149,10 @@ Change notifications are batched and subscribers get notified each microtask. It
 ```ts
 const library = Library.create({
   a: { type: DesignToken.Type.Color, value: "#000000" },
-  b: { type: DesignToken.Type.Color, value: (tokens) => tokens.a },
+  b: {
+    type: DesignToken.Type.Color,
+    value: Library.derive((tokens) => tokens.a),
+  },
 });
 
 library.subscribe({