Example: Add complete workflow configuration example (multi-platform build: windows darwin linux)

The current example only has the. gorelease.yaml part, and there is no corresponding workflow configuration. When I compile mac, it will prompt that the compiler does not exist.

Here is the build config I'm using:

  - id: desktop
    binary: golang-cross
    env:
      - CGO_ENABLED=1
      - >-
        {{- if eq .Os "darwin" }}
          {{- if eq .Arch "amd64"}}CC=o64-clang{{- end }}
          {{- if eq .Arch "arm64"}}CC=aarch64-apple-darwin20.2-clang{{- end }}
        {{- end }}
        {{- if eq .Os "windows" }}
          {{- if eq .Arch "amd64" }}CC=x86_64-w64-mingw32-gcc{{- end }}
          {{- if eq .Arch "arm64" }}CC=/llvm-mingw/bin/aarch64-w64-mingw32-gcc{{- end }}          
          {{- if eq .Arch "386" }}CC=i686-w64-mingw32-gcc{{- end }}
        {{- end }}
      - >-
        {{- if eq .Os "darwin" }}
          {{- if eq .Arch "amd64"}}CXX=o64-clang++{{- end }}
          {{- if eq .Arch "arm64"}}CX=clang++{{- end }}
        {{- end }}
        {{- if eq .Os "windows" }}
          {{- if eq .Arch "amd64" }}CXX=x86_64-w64-mingw32-g++{{- end }}
          {{- if eq .Arch "arm64" }}CXX=/llvm-mingw/bin/aarch64-w64-mingw32-g++{{- end }}          
          {{- if eq .Arch "386" }}CXX=i686-w64-mingw32-g++{{- end }}
        {{- end }}
    goos:
      - darwin
      - windows
    main: ./cmd/desktop/main.go

The error log is as follows:

  ⨯ release failed after 2m35s              
    error=
    │ build failed: exit status 1: # runtime/cgo
    │ cgo: C compiler "o64-clang" not found: exec: "o64-clang": executable file not found in $PATH
    target=darwin_amd64_v1
Error: The process '/opt/hostedtoolcache/goreleaser-action/2.8.2/x64/goreleaser' failed with exit code 1

Start with the gorelease.yaml configuration in the issue and the ./cmd/desktop/main.go entry point; inspect how the repository's GitHub Actions workflow invokes the GoReleaser action. Add a complete workflow example covering Windows, macOS, and Linux, then verify that the cross-platform build no longer fails because the compiler is missing.