Prepare GovOPlaN self-hosted release workflow

.gitea/workflows/module-matrix.yml

@@ -17,6 +17,24 @@ jobs:
       - uses: actions/setup-node@v4
         with:
           node-version: "22"
+      - name: Configure SSH for release dependencies
+        env:
+          GOVOPLAN_RELEASE_SSH_KEY: ${{ secrets.GOVOPLAN_RELEASE_SSH_KEY }}
+        run: |
+          mkdir -p ~/.ssh
+          chmod 700 ~/.ssh
+          if [ -z "${GOVOPLAN_RELEASE_SSH_KEY:-}" ]; then
+            echo "GOVOPLAN_RELEASE_SSH_KEY secret is required for git+ssh release dependencies."
+            exit 1
+          fi
+          printf '%s\n' "$GOVOPLAN_RELEASE_SSH_KEY" > ~/.ssh/id_ed25519
+          chmod 600 ~/.ssh/id_ed25519
+          if ! command -v ssh-keyscan >/dev/null 2>&1; then
+            apt-get update
+            apt-get install -y openssh-client
+          fi
+          ssh-keyscan -4 -H git.add-ideas.de >> ~/.ssh/known_hosts
+          chmod 600 ~/.ssh/known_hosts
       - name: Install backend release dependencies
         run: |
           python -m venv .venv