docs: update example

Author: incendial

example/README.md

@@ -2,13 +2,15 @@
 
 DCM is a static analysis tool and code from it is not expected to be used directly. Instead, it should be added as a dev dependency and installed [as described here](https://dcm.dev/docs/individuals/getting-started).
 
-## Plugin and CLI
+## Preferred way: plugin and CLI
 
 To use DCM as a plugin or a CLI, check out [this repository](https://github.com/dart-code-checker/dart-code-metrics-example) with the example Flutter app. It covers DCM setup and shows all commands output.
 
-## As a library
+## Additional way: as a library
 
-DCM can be used as a library, imported and called directly from your code. Continue with [this example](https://github.com/dart-code-checker/dart-code-metrics/blob/master/example/lib/main.dart) in order to get more details.
+**Note:** usually you don't need to use DCM directly.
+
+DCM can be used directly as a library, imported and called from your code. Continue with [this example](https://github.com/dart-code-checker/dart-code-metrics-example/blob/main/lib_example/lib/main.dart) in order to get more details.
 
 ## Presets