debug: add logfire token debug logging

Author: nikhilwoodruff

src/policyengine_api/agent_sandbox.py

@@ -26,7 +26,9 @@ def configure_logfire(traceparent: str | None = None):
 
     token = os.environ.get("LOGFIRE_TOKEN", "")
     if not token:
+        print("[LOGFIRE] No LOGFIRE_TOKEN found, skipping configuration")
         return
+    print(f"[LOGFIRE] Configuring with token prefix: {token[:10]}...")
 
     logfire.configure(
         service_name="policyengine-agent",