refactor: Add make targets for cross-compilation setup

- Add setup-cross-compile target to create cargo config
- Add verify-cross-compile target to check setup
- Update CI to use make verify-cross-compile
- Simplifies CI workflow and centralizes cross-compile logic

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -45,21 +45,7 @@ jobs:
         path: target
         key: ${{ runner.os }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
     - name: Verify cross-compilation setup
-      run: |
-        echo "Installed targets:"
-        rustup target list --installed
-        echo "Cargo version:"
-        cargo --version
-        echo "Rustc version:"
-        rustc --version
-        echo "Available linkers:"
-        which x86_64-unknown-linux-musl-gcc || echo "x86_64-unknown-linux-musl-gcc not found"
-        which x86_64-linux-musl-gcc || echo "x86_64-linux-musl-gcc not found"
-        which musl-gcc || echo "musl-gcc not found"
-        which aarch64-linux-gnu-gcc || echo "aarch64-linux-gnu-gcc not found"
-        which rust-lld || echo "rust-lld not found"
-        echo "Cargo config:"
-        cat .cargo/config.toml || echo "No cargo config found"
+      run: make verify-cross-compile
     - name: Build
       run: make build-verbose
     - name: Run unit tests