Complete GoReleaser configuration with build metadata and release documentation

[Copilot]

The .goreleaser.yaml had an incomplete release: section and missing build configuration, relying on implicit defaults.

Changes

• Build configuration: Added explicit id, main, binary fields and ldflags for stripping (-s -w) and version embedding
• Release section: Added GitHub config, release mode, and installation instructions as header/footer templates
• Code formatting: Simplified struct literal in main.go

Before

builds:
  - env:
      - CGO_ENABLED=0
    goos:
      - linux
    goarch:
      - amd64
      - arm64

release:

After

builds:
  - id: adapt
    main: ./main.go
    binary: adapt
    env:
      - CGO_ENABLED=0
    goos:
      - linux
    goarch:
      - amd64
      - arm64
    ldflags:
      - -s -w
      - -X main.version={{.Version}}
      - -X main.commit={{.Commit}}
      - -X main.date={{.Date}}

release:
  github:
    owner: ericsuh
    name: adapt
  draft: false
  prerelease: auto
  mode: replace
  header: |
    ## Release {{.Version}}
    Download the appropriate archive for your system below.
  footer: |
    ## Installation
    1. Download the archive for your system
    2. Extract: `tar -xzf adapt_{{.Version}}_linux_*.tar.gz`
    3. Move to PATH: `sudo mv adapt /usr/local/bin/`
    4. Make executable: `sudo chmod +x /usr/local/bin/adapt`

This produces smaller binaries with embedded version metadata and user-friendly release notes.

Original prompt

Diagnose and fix the go build and release pipeline GitHub Actions workflow, which is currently not producing working binary executables in the releases pages.

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