Add copilot-setup-steps.yml with Java 25 and Maven caching

Co-authored-by: thomasturrell <1552612+thomasturrell@users.noreply.github.com>

Author: Copilot

.github/copilot-setup-steps.yml

@@ -0,0 +1,122 @@
+# GitHub Copilot Setup Steps for xAPI Java
+# This file configures the environment for GitHub Copilot agents working on this repository.
+# See: https://docs.github.com/en/enterprise-cloud@latest/copilot/how-tos/use-copilot-agents/coding-agent/customize-the-agent-environment
+
+steps:
+  # Step 1: Install SDKMAN (Java version manager)
+  - name: Install SDKMAN
+    shell: bash
+    run: |
+      # Install SDKMAN if not already installed
+      if [ ! -d "$HOME/.sdkman" ]; then
+        curl -s "https://get.sdkman.io" | bash
+        source "$HOME/.sdkman/bin/sdkman-init.sh"
+      else
+        source "$HOME/.sdkman/bin/sdkman-init.sh"
+      fi
+      
+      # Verify SDKMAN installation
+      sdk version
+    notes: |
+      SDKMAN is a tool for managing parallel versions of multiple Software Development Kits.
+      It's used to install and manage Java versions on Unix-based systems.
+      
+      OS-specific notes:
+      - Linux/macOS: Works out of the box
+      - Windows: Use WSL (Windows Subsystem for Linux) or Git Bash
+      - Windows alternative: Download Java 25 directly from https://adoptium.net/temurin/releases/
+
+  # Step 2: Install Java 25 using SDKMAN
+  - name: Install Java 25
+    shell: bash
+    run: |
+      # Source SDKMAN
+      source "$HOME/.sdkman/bin/sdkman-init.sh"
+      
+      # Install Java 25 (Temurin distribution)
+      # The exact version identifier may vary by platform
+      sdk install java 25.0.1-tem || sdk install java 25.0.0-tem || sdk install java 25-tem
+      
+      # Set Java 25 as the default version for this shell
+      sdk use java 25.0.1-tem || sdk use java 25.0.0-tem || sdk use java 25-tem
+      
+      # Verify Java installation
+      java -version
+      
+      # Verify Maven can use Java 25
+      ./mvnw --version
+    notes: |
+      Java 25 or newer is required for this project.
+      
+      OS-specific notes:
+      - The exact Java 25 identifier varies by platform and availability
+      - Use 'sdk list java' to see available Java 25 versions for your system
+      - Common identifiers: 25.0.1-tem, 25.0.0-tem, 25-tem
+      - For Windows without WSL, download from https://adoptium.net/temurin/releases/?version=25
+
+  # Step 3: Download and cache Maven dependencies
+  - name: Download Maven dependencies
+    shell: bash
+    run: |
+      # Source SDKMAN to ensure Java 25 is active
+      source "$HOME/.sdkman/bin/sdkman-init.sh"
+      sdk use java 25.0.1-tem || sdk use java 25.0.0-tem || sdk use java 25-tem
+      
+      # Download dependencies without running tests
+      # This populates the local Maven cache (~/.m2/repository)
+      ./mvnw dependency:go-offline -DskipTests
+      
+      # Alternative: Download and compile without running tests
+      ./mvnw clean compile -DskipTests
+    notes: |
+      Maven dependencies are cached in ~/.m2/repository directory.
+      This step downloads all required dependencies to avoid repeated downloads.
+      
+      Key dependencies include:
+      - Spring Boot 3.5.7
+      - Spring WebClient (reactive)
+      - Jackson (JSON serialization)
+      - Lombok (code generation)
+      - JUnit 5 (testing)
+      - Hamcrest (assertions)
+      - OkHttp (HTTP client for testing)
+      - CheckStyle (code style enforcement)
+      
+      Cache location:
+      - Linux/macOS: ~/.m2/repository
+      - Windows: %USERPROFILE%\.m2\repository
+
+  # Step 4: Verify the environment setup
+  - name: Verify build environment
+    shell: bash
+    run: |
+      # Source SDKMAN to ensure Java 25 is active
+      source "$HOME/.sdkman/bin/sdkman-init.sh"
+      sdk use java 25.0.1-tem || sdk use java 25.0.0-tem || sdk use java 25-tem
+      
+      # Run a clean build with tests to verify everything works
+      ./mvnw clean verify
+    notes: |
+      This step verifies that the environment is properly configured by running
+      a full build including CheckStyle validation and all tests.
+      
+      Build process includes:
+      - CheckStyle validation (Google Java Style Guide)
+      - Compilation of all modules (xapi-model, xapi-client, samples, xapi-model-spring-boot-starter)
+      - Unit tests (300+ tests)
+      - Integration tests
+      - Code coverage analysis (JaCoCo)
+      
+      Expected duration: 2-3 minutes on first run, faster with cached dependencies
+      
+      Troubleshooting:
+      - If build fails with "release version 25 not supported", verify Java 25 is active with 'java -version'
+      - If dependencies fail to download, check network connectivity
+      - If tests fail, this may indicate an environment-specific issue
+
+# Cache configuration
+cache:
+  - path: ~/.m2/repository
+    key: maven-${{ runner.os }}-${{ hashFiles('**/pom.xml') }}
+    restore-keys: |
+      maven-${{ runner.os }}-