feat: Add comprehensive integration test coverage

.gitignore

@@ -272,3 +272,5 @@ src/main/resources/
 /src/main/java/com/contentstack/sdk/models/
 /.vscode/
 /.vscode/
+/docs/
+INTEGRATION-TESTS-GUIDE.md

pom.xml

@@ -277,13 +277,38 @@
                 <artifactId>maven-surefire-plugin</artifactId>
                 <version>2.22.2</version>
                 <configuration>
-                    <!-- Run only API tests (*IT.java) by default -->
-                    <includes>
-                        <include>**/*IT.java</include>
-                    </includes>
+                    <!-- Tests are skipped by default; use -Dtest to specify which tests to run -->
+                    <!-- Example: -Dtest='*IT' for integration tests, -Dtest='Test*' for unit tests -->
                     <skipTests>true</skipTests>
+                    <!-- OPTIMIZED: Parallel execution with controlled concurrency -->
+                    <parallel>classes</parallel>
+                    <threadCount>4</threadCount>
+                    <perCoreThreadCount>false</perCoreThreadCount>
+                    <useUnlimitedThreads>false</useUnlimitedThreads>
+                    <!-- Reuse forks for better performance -->
+                    <reuseForks>true</reuseForks>
+                    <forkCount>2</forkCount>
+                    <!-- Increase timeout for slow tests -->
+                    <forkedProcessTimeoutInSeconds>500</forkedProcessTimeoutInSeconds>
+                    <!-- Better memory management -->
+                    <!-- @{argLine} allows JaCoCo to inject its agent -->
+                    <argLine>@{argLine} -Xmx2048m -XX:MaxMetaspaceSize=512m</argLine>
                 </configuration>
             </plugin>
+
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-report-plugin</artifactId>
+                <version>2.22.2</version>
+                <executions>
+                    <execution>
+                        <phase>test</phase>
+                        <goals>
+                            <goal>report-only</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
 
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
@@ -382,7 +407,7 @@
                         </goals>
                         <configuration>
                             <dataFile>target/jacoco.exec</dataFile>
-                            <outputDirectory>target/jacoco-ut</outputDirectory>
+                            <!-- outputDirectory removed - uses default: target/site/jacoco/ -->
                         </configuration>
                     </execution>
                 </executions>