Examine source code of Claude Busy Blocker

{
  "manifest_version": 3,
  "name": "Claude Busy Blocker",
  "version": "0.1.0",
  "description": "Blocks distracting sites unless Claude Code is actively generating a response.",
  "browser_specific_settings": {
    "gecko": {
      "id": "claude-busy-blocker@local",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "declarativeNetRequest",
    "storage",
    "alarms"
  ],
  "host_permissions": [
    "http://127.0.0.1/*",
    "http://localhost/*"
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'; connect-src 'self' http://127.0.0.1:9999 http://localhost:9999"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "action": {
    "default_title": "Claude Busy Blocker",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  }
}