Migrate build infrastructure from Gradle to Maven

- Add pom.xml with all dependencies, compiler settings (Java 1.8, -parameters),
  jar manifest (Automatic-Module-Name), javadoc, source, and GPG signing profile
- Add Maven wrapper (mvnw/mvnw.cmd) replacing Gradle wrapper
- Rename gradle-build.yml to maven-build.yml with Maven commands and cache
- Update codeql-analysis.yml to use mvnw compile
- Update ADO ci-build.yml with Maven install/deploy and settings.xml auth
- Update ADO daily-ci-build.yml with Maven@4 task and network-isolated mirror
- Update dependabot.yml: maven ecosystem for root, gradle kept for /android
- Update .gitignore: swap Gradle entries for Maven
- Update release-please-config.json: XML xpath updater for pom.xml version
- Inline dependencies into android/build.gradle (remove shared gradle/dependencies.gradle)
- Remove all root Gradle files and java-8/ sub-project

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: ramsessanchez

.github/workflows/gradle-build.yml .github/workflows/maven-build.yml.github/workflows/gradle-build.yml renamed to .github/workflows/maven-build.yml

@@ -1,4 +1,4 @@
-name: Gradle Build and Compare Package
+name: Maven Build
 
 on:
   push:
@@ -17,36 +17,29 @@ jobs:
         with:
           java-version: 21
           distribution: 'temurin'
-          cache: gradle
+          cache: maven
       - name: Move generated sources to correct package
         run: .\scripts\copyFilesOnBuild.ps1 -inputPath '.\src\main\java\com\microsoft\graph\generated'
         shell: pwsh
-      - name: Grant Execute permission for gradlew
-        run: chmod +x gradlew
-      - name: Build with Gradle
-        run: ./gradlew build
+      - name: Build with Maven
+        run: ./mvnw verify --no-transfer-progress
       - name: Upload Unit Test Results
         if: ${{ always() }}
         uses: actions/upload-artifact@v7
         with:
           name: UnitTests
           path: |
-            build/reports/tests/test/**
-            build/test-results/**
+            target/surefire-reports/**
       - name: Upload a Build Artifact
         uses: actions/upload-artifact@v7
         with:
           name: drop
           path: |
-            **/libs/*
-            build/generated-pom.xml
-            build/generated-pom.xml.asc
-            build.gradle
-            gradlew
-            gradlew.bat
-            settings.gradle
-            gradle.properties
-            **/gradle/**
+            target/*.jar
+            pom.xml
+            mvnw
+            mvnw.cmd
+            .mvn/**
             scripts/**
 
   build-java-8:
@@ -58,15 +51,12 @@ jobs:
         with:
           java-version: 8
           distribution: 'temurin'
-          cache: gradle
+          cache: maven
       - name: Move generated sources to correct package
         run: .\scripts\copyFilesOnBuild.ps1 -inputPath '.\src\main\java\com\microsoft\graph\generated'
         shell: pwsh
-      - name: Grant Execute permission for gradlew
-        run: chmod +x gradlew
       - name: Build with Java 8
-        working-directory: ./java-8
-        run: .././gradlew build
+        run: ./mvnw compile --no-transfer-progress
 
   build:
     needs: [build-java-latest, build-java-8]
@@ -81,19 +71,3 @@ jobs:
             exit 1
           fi
 
-  dependency-submission:
-    runs-on: ubuntu-latest
-    if: github.event_name == 'push'
-    permissions:
-      contents: write
-    steps:
-      - uses: actions/checkout@v6
-      - name: Set up JDK
-        uses: actions/setup-java@v5
-        with:
-          java-version: 21
-          distribution: 'temurin'
-          cache: gradle
-      - name: Generate and submit dependency graph
-        uses: gradle/actions/dependency-submission@v6
-

.mvn/wrapper/maven-wrapper.jar

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.9/apache-maven-3.9.9-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.3.2/maven-wrapper-3.3.2.jar