chore(mcp): empty local .mcp.json after SSE migration

stdio server entry no longer needed here; MCP server is registered
at user scope via ~/.claude.json (SSE on :8001).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.mcp.json

@@ -1,13 +1,3 @@
 {
-  "mcpServers": {
+  "mcpServers": {}
-    "state-hub": {
-      "type": "stdio",
-      "command": "/home/worsch/the-custodian/state-hub/.venv/bin/python",
-      "args": ["/home/worsch/the-custodian/state-hub/mcp_server/server.py"],
-      "env": {
-        "PYTHONPATH": "/home/worsch/the-custodian/state-hub",
-        "API_BASE": "http://127.0.0.1:8000"
-      }
-    }
-  }
 }