fix(core,tooling): keep the harness's own ports out of the Agent's environment and off the dev server (#100)

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: J.Li <jl2388@cam.ac.uk>

packages/cli/package.json

@@ -19,7 +19,7 @@
     "typecheck": "tsc --noEmit -p tsconfig.json",
     "test": "vitest run --passWithNoTests",
     "build": "tsup",
-    "penguin": "node ../../scripts/run-with-env.mjs PENGUIN_HOME=~/.penguin/dev-data -- tsx src/index.ts"
+    "penguin": "node ../../scripts/run-with-env.mjs PENGUIN_HOME=~/.penguin/dev-data PORT=7369 -- tsx src/index.ts"
   },
   "dependencies": {
     "@prismshadow/agenthub": "^0.4.1",