fix: resolve zstd-sys compilation issues with zig cross-compilation (#203)

- Update to mlugg/setup-zig@v2 for better stability and features
- Use Zig 0.13.0 for improved musl target support
- Add system zstd libraries (libzstd-dev, zstd) to Ubuntu dependencies
- Configure environment variables for zstd-sys to use pkg-config
- Enable pkg-config feature for zstd dependency to prefer system library
- Add proper C/C++ compiler configuration for musl targets

Fixes the 'error: unable to parse target query x86_64-unknown-linux-musl: UnknownOperatingSystem'
compilation error in zstd-sys during cross-compilation.

.github/actions/setup/action.yml

@@ -58,7 +58,9 @@ runs:
           libwebkit2gtk-4.1-dev \
           libxdo-dev \
           pkg-config \
-          libssl-dev
+          libssl-dev \
+          libzstd-dev \
+          zstd
 
     - name: Install protoc
       uses: arduino/setup-protoc@v3
@@ -81,6 +83,8 @@ runs:
     - name: Install Zig
       if: inputs.install-cross-tools == 'true'
       uses: mlugg/setup-zig@v2
+      with:
+        version: 0.13.0
 
     - name: Install cargo-zigbuild
       if: inputs.install-cross-tools == 'true'

.github/workflows/build.yml

@@ -191,6 +191,17 @@ jobs:
         run: |
           # Use unified build script for consistent builds
           ./build-rustfs.sh --platform ${{ matrix.target }}
+        env:
+          # Set environment variables for zstd-sys to avoid target parsing issues
+          ZSTD_SYS_USE_PKG_CONFIG: 1
+          PKG_CONFIG_ALLOW_CROSS: 1
+          # For musl targets, use system zstd if available
+          CC_x86_64_unknown_linux_musl: zig cc -target x86_64-linux-musl
+          CXX_x86_64_unknown_linux_musl: zig c++ -target x86_64-linux-musl
+          AR_x86_64_unknown_linux_musl: zig ar
+          CC_aarch64_unknown_linux_musl: zig cc -target aarch64-linux-musl
+          CXX_aarch64_unknown_linux_musl: zig c++ -target aarch64-linux-musl
+          AR_aarch64_unknown_linux_musl: zig ar
 
       - name: Create release package
         id: package