feat: add native/Java auth SDK, docs, CI, and examples

Made-with: Cursor

.github/workflows/ci-native.yml

@@ -0,0 +1,40 @@
+name: ci-native
+
+on:
+  push:
+    branches: [main, master]
+  pull_request:
+    branches: [main, master]
+
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up JDK (JNI)
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: "17"
+      - name: Configure & build (Unix)
+        if: runner.os != 'Windows'
+        run: |
+          cmake -S native -B native/build -DCMAKE_BUILD_TYPE=Release
+          cmake --build native/build --parallel
+      - name: Configure & build (Windows)
+        if: runner.os == 'Windows'
+        run: |
+          cmake -S native -B native/build -DCMAKE_BUILD_TYPE=Release
+          cmake --build native/build --config Release --parallel
+      - name: Test (Unix)
+        if: runner.os != 'Windows'
+        working-directory: native/build
+        run: ctest --output-on-failure
+      - name: Test (Windows)
+        if: runner.os == 'Windows'
+        working-directory: native/build
+        run: ctest -C Release --output-on-failure