feat(sdk): AuthConfigs, JSON Schema, examples, and release checksum CI

Add craftlabs-auth-config.schema.json, Java AuthConfigs model with tests,
example configs aligned to BP-10, C/Java/auth-config documentation,
native header notes, RELEASING guide, and workflow to verify SDK
artifact checksums on release tags.

Made-with: Cursor

.github/workflows/sdk-release-checksums.yml

@@ -0,0 +1,39 @@
+# 手动触发：打包 SDK + Native(.so) 并生成 SHA256SUMS，供 GitHub Release 上传
+name: sdk-release-checksums
+
+on:
+  workflow_dispatch:
+
+jobs:
+  checksums:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: "17"
+          cache: maven
+      - name: Install native build deps
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y build-essential cmake
+      - name: Build native (.so)
+        run: |
+          cmake -S native -B native/build -DCMAKE_BUILD_TYPE=Release -DCRAFTLABS_BUILD_JNI=ON
+          cmake --build native/build --parallel
+      - name: Maven package (SDK jars)
+        run: mvn -f java/pom.xml -B -DskipTests package
+      - name: Generate SHA256SUMS
+        run: |
+          chmod +x scripts/sdk-release-checksums.sh
+          ./scripts/sdk-release-checksums.sh --no-mvn --output dist/sdk-release --native-path "${{ github.workspace }}/native/build"
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: sdk-release-${{ github.ref_name }}
+          path: |
+            dist/sdk-release/
+            java/craftlabs-auth-core/target/*.jar
+            java/craftlabs-auth-bitanswer/target/*.jar
+            java/craftlabs-auth-selfhosted/target/*.jar