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/escape-html/package.json

@@ -0,0 +1,24 @@
+{
+  "name": "escape-html",
+  "description": "Escape string for use in HTML",
+  "version": "1.0.3",
+  "license": "MIT",
+  "keywords": [
+    "escape",
+    "html",
+    "utility"
+  ],
+  "repository": "component/escape-html",
+  "devDependencies": {
+    "benchmark": "1.0.0",
+    "beautify-benchmark": "0.2.4"
+  },
+  "files": [
+    "LICENSE",
+    "Readme.md",
+    "index.js"
+  ],
+  "scripts": {
+    "bench": "node benchmark/index.js"
+  }
+}