Fix: Use correct health check endpoints for LiteLLM and Letta

Root cause: Status API was using wrong health endpoints:
- LiteLLM /health requires API key auth (returns 401) -> changed to /health/readiness (no auth)
- Letta /api/health returns 404 -> changed to /v1/health/ (correct endpoint)

package.json

@@ -0,0 +1,13 @@
+{
+  "name": "apex-status-api",
+  "version": "1.0.0",
+  "description": "APEX OS Platform Health Monitor",
+  "main": "server.js",
+  "scripts": {
+    "start": "node server.js",
+    "test": "node test.js"
+  },
+  "dependencies": {
+    "express": "^4.18.0"
+  }
+}