feat: plan per-user memory integration

config/users.json

@@ -0,0 +1,15 @@
+{
+  "version": 1,
+  "users": {
+    "shane": {
+      "display_name": "Shane",
+      "livekit_identity": "shane",
+      "memory": {
+        "url": "http://192.168.86.2:8790/mcp",
+        "api_key": "sm_93a2edf391e15592a96b00d58ea7dfca1a1e53b34287ff44",
+        "remote_username": "pi",
+        "remote_token_label": "voice-agent"
+      }
+    }
+  }
+}