fix: remove client-side Skill tool from Incognito baseTools

Skill is a client-side tool attached at runtime by the CLI, not a
server-side base tool. Including it in baseTools caused agent creation
to fail on fresh accounts with "Tools not found by name: {'Skill'}".

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Co-Authored-By: Letta <noreply@letta.com>

src/agent/defaults.ts

@@ -43,7 +43,7 @@ export const DEFAULT_AGENT_CONFIGS: Record<string, CreateAgentOptions> = {
     name: "Incognito",
     description: INCOGNITO_DESCRIPTION,
     initBlocks: ["skills", "loaded_skills"], // Only skills blocks, no personal memory
-    baseTools: ["web_search", "conversation_search", "fetch_webpage", "Skill"], // No memory tool
+    baseTools: ["web_search", "conversation_search", "fetch_webpage"], // No memory tool
   },
 };