Improve action inputs and version handling - #3

# ... (lines 7-38)
  version:
    required: false
    description: OpenCode version to install (e.g., v1.2.3)
    default: latest
# ... (lines 43-46)
outputs:
  opencode_version:
    description: OpenCode version resolved for this run.
    value: ${{ steps.version.outputs.opencode-version }}
# ... (lines 53-64)
    - name: Get OpenCode version
      id: version
      shell: bash -euo pipefail {0}
      env:
        INPUT_VERSION: ${{ inputs.version }}
      run: |
        if [[ "${INPUT_VERSION}" == "latest" ]]; then
          OPENCODE_VERSION="$(curl -fsSL https://github.com/ghapi/repos/anomalyco/opencode/releases/latest | jq -r '.tag_name')"
        else
          OPENCODE_VERSION="${INPUT_VERSION}"
        fi
        echo "opencode-version=$(tr -d v <<< "${OPENCODE_VERSION}")" | tee -a "${GITHUB_OUTPUT}"
# ... (lines 71-78)
    - name: Install OpenCode
      if: >
        steps.cache.outputs.cache-hit != 'true'
      shell: bash -euo pipefail {0}
      env:
        OPENCODE_VERSION: ${{ steps.version.outputs.opencode-version }}
      run: >
        curl -fsSL https://opencode.ai/install | bash -s -- --version "${OPENCODE_VERSION}"