ci(kmp): set ANDROID_SDK_ROOT and write local.properties

Set the ANDROID_SDK_ROOT environment variable and generate local.properties in the KMP test workflow to ensure correct Android SDK path usage.

Author: phodal

.github/workflows/kmp-test.yml

@@ -27,6 +27,8 @@ jobs:
   test-mpp-core:
     name: Test mpp-core (KMP)
     runs-on: ubuntu-latest
+    env:
+      ANDROID_SDK_ROOT: ${{ github.workspace }}/android-sdk
     steps:
       # Free GitHub Actions Environment Disk Space
       - name: Maximize Build Space
@@ -58,6 +60,9 @@ jobs:
         run: |
           yes | $ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager --licenses || true
 
+      - name: Write local.properties
+        run: echo "sdk.dir=${ANDROID_SDK_ROOT}" > local.properties
+
       # Setup Gradle
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4