fix: add userConfig for CoWork credential prompting

CoWork runs in a VM where shell env vars aren't available. Add
userConfig to plugin.json so Claude prompts for credentials when
the plugin is enabled. Sensitive values stored in system keychain.

- Add helpscout_app_id, helpscout_app_secret, redact_message_content
  to userConfig in plugin.json
- Update .mcp.json to use ${user_config.*} substitutions

Author: drewburchfield

plugins/helpscout-navigator/.claude-plugin/plugin.json

@@ -16,5 +16,19 @@
     "mcp",
     "customer-service",
     "inbox"
-  ]
+  ],
+  "userConfig": {
+    "helpscout_app_id": {
+      "description": "Help Scout App ID (from My Apps > Your App)",
+      "sensitive": true
+    },
+    "helpscout_app_secret": {
+      "description": "Help Scout App Secret (from My Apps > Your App)",
+      "sensitive": true
+    },
+    "redact_message_content": {
+      "description": "Redact message content for privacy (true/false)",
+      "sensitive": false
+    }
+  }
 }

plugins/helpscout-navigator/.mcp.json

@@ -3,9 +3,9 @@
     "command": "npx",
     "args": ["-y", "help-scout-mcp-server"],
     "env": {
-      "HELPSCOUT_APP_ID": "${HELPSCOUT_APP_ID}",
-      "HELPSCOUT_APP_SECRET": "${HELPSCOUT_APP_SECRET}",
-      "REDACT_MESSAGE_CONTENT": "${REDACT_MESSAGE_CONTENT:-false}"
+      "HELPSCOUT_APP_ID": "${user_config.helpscout_app_id}",
+      "HELPSCOUT_APP_SECRET": "${user_config.helpscout_app_secret}",
+      "REDACT_MESSAGE_CONTENT": "${user_config.redact_message_content}"
     }
   }
 }