Add GitHub Actions release workflow for cross-compiled binaries

Builds for x86_64 and aarch64 on both Linux and macOS. Triggered on
version tags (v*). Uses cross for aarch64-linux cross-compilation.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: c

.github/workflows/release.yml

@@ -0,0 +1,86 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+    strategy:
+      matrix:
+        include:
+          - target: x86_64-unknown-linux-gnu
+            os: ubuntu-latest
+            use_cross: false
+          - target: aarch64-unknown-linux-gnu
+            os: ubuntu-latest
+            use_cross: true
+          - target: aarch64-apple-darwin
+            os: macos-latest
+            use_cross: false
+          - target: x86_64-apple-darwin
+            os: macos-13
+            use_cross: false
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: ${{ matrix.target }}
+
+      - name: Install cross
+        if: matrix.use_cross
+        run: cargo install cross --locked
+
+      - name: Build
+        run: |
+          if [ "${{ matrix.use_cross }}" = "true" ]; then
+            cross build --release --target ${{ matrix.target }}
+          else
+            cargo build --release --target ${{ matrix.target }}
+          fi
+
+      - name: Package
+        run: |
+          VERSION="${GITHUB_REF_NAME}"
+          ARCHIVE="sqssh-${VERSION}-${{ matrix.target }}.tar.gz"
+          BINDIR="target/${{ matrix.target }}/release"
+
+          BINS=""
+          for bin in sqssh sqsshd sqscp sqsftp sqssh-keygen sqssh-keyscan sqssh-agent sqssh-add sqssh-copy-id sqsshctl sqssh-persist; do
+            if [ -f "${BINDIR}/${bin}" ]; then
+              BINS="${BINS} ${BINDIR}/${bin}"
+            fi
+          done
+
+          tar -czf "${ARCHIVE}" -C "${BINDIR}" $(for b in $BINS; do basename "$b"; done)
+          echo "ARCHIVE=${ARCHIVE}" >> $GITHUB_ENV
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: sqssh-${{ matrix.target }}
+          path: ${{ env.ARCHIVE }}
+
+  release:
+    needs: build
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+
+    steps:
+      - uses: actions/download-artifact@v4
+        with:
+          merge-multiple: true
+
+      - name: Create Release
+        uses: softprops/action-gh-release@v2
+        with:
+          generate_release_notes: true
+          files: sqssh-*.tar.gz