docs: add 'mode' field to create_plugin MCP tool schema

app/src/main/java/com/nonvioce/ijs/McpServer.java

@@ -276,6 +276,7 @@ public class McpServer extends NanoHTTPD {
                         "returns a Symja expression string"))
                     .put("icon", stringProp("Emoji icon (optional, default: 🔌)"))
                     .put("command", stringProp("Short command name (optional, e.g. 'circle')"))
+                    .put("mode", stringProp("Display mode: 'inline' (dialog, default) or 'fullscreen' (interactive panel)"))
                     .put("description", stringProp("Plugin description (optional)"))
                     .put("inputs", stringProp(
                         "JSON array of input definitions (optional). " +