ci: add java and android prepare

.forgejo/workflows/build.yaml

@@ -14,6 +14,15 @@ jobs:
         with:
           submodules: recursive
 
+      - name: Set up JDK 21
+        uses: https://github.com/actions/setup-java@v3
+        with:
+          java-version: "21"
+          distribution: "temurin"
+
+      - name: Setup Android SDK
+        uses: https://github.com/android-actions/setup-android@v3
+
       # 2. Устанавливаем Flutter из подмодуля
       - name: Setup Flutter
         run: |