Update @woo…/number code docs, define & export type declarations.

packages/number/src/index.js

@@ -1,15 +1,21 @@
 const numberFormatter = require( 'locutus/php/strings/number_format' );
 
+/**
+ * Number formatting configuration object
+ *
+ * @typedef {Object} NumberConfig
+ * @property {number} [precision] Decimal precision.
+ * @property {string} [decimalSeparator] Decimal separator.
+ * @property {string} [thousandSeparator] Character used to separate thousands groups.
+ */
+
 /**
  * Formats a number using site's current locale
  *
  * @see http://locutus.io/php/strings/number_format/
- * @param {Object} numberConfig number formatting configuration object.
- * @param {number} numberConfig.precision
- * @param {string} numberConfig.decimalSeparator
- * @param {string} numberConfig.thousandSeparator
+ * @param {NumberConfig} numberConfig Number formatting configuration object.
  * @param {number|string} number number to format
- * @return {?string} A formatted string.
+ * @return {string} A formatted string.
  */
 export function numberFormat(
 	{ precision = null, decimalSeparator = '.', thousandSeparator = ',' },
@@ -39,12 +45,14 @@ export function numberFormat(
 }
 
 /**
- * Formats a number string based on type of `average` or `number`.
+ * Formats a number as average or number string according to the given `type`.
+ *  - `type = 'average'` returns a rounded `Number`
+ *  - `type = 'number'` returns a formatted `String`
  *
- * @param {Object} numberConfig number formatting configuration object.
- * @param {string} type of number to format, average or number
+ * @param {NumberConfig} numberConfig number formatting configuration object.
+ * @param {string} type of number to format, `'average'` or `'number'`
  * @param {number} value to format.
- * @return {?string} A formatted string.
+ * @return {string | number | null} A formatted string.
  */
 export function formatValue( numberConfig, type, value ) {
 	if ( ! Number.isFinite( value ) ) {

packages/number/tsconfig-cjs.json

@@ -1,6 +1,7 @@
 {
     "extends": "../tsconfig-cjs",
     "compilerOptions": {
+		"declaration": true,
         "outDir": "build"
     }
 }

packages/number/tsconfig.json

@@ -1,6 +1,7 @@
 {
 	"extends": "../tsconfig",
 	"compilerOptions": {
+		"declaration": true,
 		"rootDir": "src",
 		"outDir": "build-module"
 	}