ALEC-295: Gate RegressionIT behind a demo-it Maven profile

cgorantla's review on PR #153 noted that RegressionIT depends on a
live OpenNMS+ALEC instance and was running unconditionally as part of
the default verify lifecycle. CI pipelines have no live OpenNMS to
talk to, so the tests would fail (silently, in some configurations)
on every run.

Move the maven-failsafe-plugin execution into a new "demo-it" profile
that is OFF by default. Default behaviour now:

  mvn -pl demo -am verify         # builds, runs unit tests, no IT
  mvn -pl demo -am verify -Pdemo-it ... # opt-in: runs RegressionIT

surefire still excludes **/*IT.java in the default phase, so unit
tests in this module continue to run unaffected.

README updated with the new invocation.

Author: joseanesONMS

demo/README.md

@@ -127,10 +127,15 @@ OpenNMS topology view and ALEC's correlation graph.
 
 ## Regression Tests (Integration)
 
-Requires a running OpenNMS+ALEC instance:
+`RegressionIT` requires a live OpenNMS+ALEC instance, so it is **not** bound
+to the default `verify` lifecycle (CI pipelines won't try to run it). Activate
+the `demo-it` profile to opt in:
 
 ```bash
-mvn verify -pl demo -Dopennms.url=http://localhost:8980/opennms
+mvn verify -pl demo -am -Pdemo-it \
+    -Dopennms.url=http://localhost:8980/opennms \
+    -Dopennms.username=admin \
+    -Dopennms.password=admin
 ```
 
 ## Engine-Level Tests (No OpenNMS Needed)

demo/pom.xml

@@ -26,7 +26,8 @@
                     <target>${java.version}</target>
                 </configuration>
             </plugin>
-            <!-- Skip integration tests by default -->
+            <!-- Skip *IT.java in surefire — they are run only by the
+                 demo-it profile via failsafe (see <profiles> below). -->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
@@ -36,25 +37,6 @@
                     </excludes>
                 </configuration>
             </plugin>
-            <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-failsafe-plugin</artifactId>
-                <configuration>
-                    <systemPropertyVariables>
-                        <opennms.url>${opennms.url}</opennms.url>
-                        <opennms.username>${opennms.username}</opennms.username>
-                        <opennms.password>${opennms.password}</opennms.password>
-                    </systemPropertyVariables>
-                </configuration>
-                <executions>
-                    <execution>
-                        <goals>
-                            <goal>integration-test</goal>
-                            <goal>verify</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
             <!-- Make executable jar -->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
@@ -169,4 +151,44 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
+
+    <!--
+        Integration tests in this module (RegressionIT) require a live
+        OpenNMS+ALEC instance to talk to. They are intentionally NOT bound
+        to the default verify lifecycle so a normal CI pipeline does not
+        try to run them. To run them locally:
+
+            mvn -pl demo -am verify -Pdemo-it \
+                -Dopennms.url=http://localhost:8980/opennms \
+                -Dopennms.username=admin \
+                -Dopennms.password=admin
+    -->
+    <profiles>
+        <profile>
+            <id>demo-it</id>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-failsafe-plugin</artifactId>
+                        <configuration>
+                            <systemPropertyVariables>
+                                <opennms.url>${opennms.url}</opennms.url>
+                                <opennms.username>${opennms.username}</opennms.username>
+                                <opennms.password>${opennms.password}</opennms.password>
+                            </systemPropertyVariables>
+                        </configuration>
+                        <executions>
+                            <execution>
+                                <goals>
+                                    <goal>integration-test</goal>
+                                    <goal>verify</goal>
+                                </goals>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
 </project>