Pre-launch fixes: error handling, cleanup, consistency

- Remove unused claude-agent-sdk from host deps (only used in container)
- Remove dead scheduler MCP config (built into IPC)
- Remove unused eslint script
- Add clear error message when Apple Container fails to start
- Auto-generate launchd plist with real paths in setup skill
- Standardize Node.js version to 20+ everywhere

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -9,11 +9,9 @@
     "start": "node dist/index.js",
     "dev": "tsx src/index.ts",
     "auth": "tsx src/whatsapp-auth.ts",
-    "lint": "eslint src/",
     "typecheck": "tsc --noEmit"
   },
   "dependencies": {
-    "@anthropic-ai/claude-agent-sdk": "^0.1.0",
     "@whiskeysockets/baileys": "^7.0.0-rc.9",
     "better-sqlite3": "^11.8.1",
     "cron-parser": "^5.5.0",
@@ -30,6 +28,6 @@
     "typescript": "^5.7.0"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=20"
   }
 }