Update README with install health check instructions (#3196)

Added instructions for checking install health with npx.

.adal/README.md

@@ -20,3 +20,4 @@ bash ./install.sh --target adal --profile minimal
 - The `adal` target installs into the project-level `./.adal/` directory.
 - AdaL's own config (`~/.adal/settings.json`, MCP servers, plugins) is **not** touched by ECC install.
 - Use `npx ecc-universal doctor --target adal` to check install health.
+- use an installed