GH-268 - Rename actuator endpoint to modulith.

To align with the conventions established by Spring Boot.

spring-modulith-actuator/src/main/java/org/springframework/modulith/actuator/ApplicationModulesEndpoint.java

@@ -32,7 +32,7 @@ import org.springframework.util.function.SingletonSupplier;
  *
  * @author Oliver Drotbohm
  */
-@Endpoint(id = "application-modules")
+@Endpoint(id = "modulith")
 public class ApplicationModulesEndpoint {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(ApplicationModulesEndpoint.class);

src/docs/asciidoc/80-observability.adoc

@@ -44,7 +44,7 @@ To enable the actuator, add the `spring-modulith-actuator` dependency to the pro
 </dependency>
 ----
 
-Running the application will now expose an `applicationmodules` actuator resource:
+Running the application will now expose an `modulith` actuator resource:
 
 .Accessing the actuator HTTP resource
 [source, json]
@@ -65,16 +65,16 @@ GET http://localhost:8080/actuator
       "href": "http://localhost:8080/actuator/health",
       "templated": false
     },
-    "applicationmodules": { <1>
-      "href": "http://localhost:8080/actuator/applicationmodules",
+    "modulith": { <1>
+      "href": "http://localhost:8080/actuator/modulith",
       "templated": false
     }
   }
 }
 ----
-<1> The `applicationmodules` actuator resource advertised.
+<1> The `modulith` actuator resource advertised.
 
-The `applicationmodules` resource adheres to the following structure:
+The `modulith` resource adheres to the following structure:
 
 .The JSON structure of the application modules actuator
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