feat(API-11): Route API calls through AgilitonAPI gateway

Add gateway-first pattern: when AGILITON_API_KEY is set, route all
external API calls through the gateway with X-API-Key auth. Falls back
to direct API access when gateway is unavailable.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

node_modules/toidentifier/index.js

@@ -0,0 +1,32 @@
+/*!
+ * toidentifier
+ * Copyright(c) 2016 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module exports.
+ * @public
+ */
+
+module.exports = toIdentifier
+
+/**
+ * Trasform the given string into a JavaScript identifier
+ *
+ * @param {string} str
+ * @returns {string}
+ * @public
+ */
+
+function toIdentifier (str) {
+  return str
+    .split(' ')
+    .map(function (token) {
+      return token.slice(0, 1).toUpperCase() + token.slice(1)
+    })
+    .join('')
+    .replace(/[^ _0-9a-z]/gi, '')
+}