fix(gateway): prevent unnecessary restart on meta.lastTouchedAt changes

When tools modify the config (e.g., `moltbot agents add`), the
meta.lastTouchedAt field gets updated. Without a reload rule for
"meta", this fell through to restartGateway=true, killing in-flight
LLM requests and causing the agent to never respond.

Added `{ prefix: "meta", kind: "none" }` to BASE_RELOAD_RULES_TAIL
so meta field changes are ignored by the reload logic.

Fixes #3811

src/gateway/config-reload.ts

@@ -82,6 +82,7 @@ const BASE_RELOAD_RULES_TAIL: ReloadRule[] = [
   { prefix: "gateway", kind: "restart" },
   { prefix: "discovery", kind: "restart" },
   { prefix: "canvasHost", kind: "restart" },
+  { prefix: "meta", kind: "none" },
 ];
 
 let cachedReloadRules: ReloadRule[] | null = null;