Allow reading the API key from the environment

[theo-m]

Hey there, love the project!

I'd like to set up our Claude review github action with your Claude code action, but I'm missing something to pass it the api key.

Your system relies solely on the fs, meaning I need to add an extra step to push my credentials in a file, all this from within the confines of a yaml file, which is uncomfortable at best.

Here's where I'd like to go

jobs:
  claude-review:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
      issues: write
      id-token: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v6
        with:
          fetch-depth: 1
      - name: Run Claude Code Review
        id: claude-review
        uses: anthropics/claude-code-action@v1
        env:
          LINEAR_WORKSPACE: xxx
          LINEAR_TEAM_ID: xxx
          LINEAR_ISSUE_SORT: priority
          // ⬇️ here
          // LINEAR_API_KEY: ${{ secrets.LINEAR_API_KEY }}
        with:
          claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
          plugin_marketplaces: "https://github.com/anthropics/claude-code.git"
          plugins: "code-review@claude-code-plugins\nlinear-cli@linear-cli"
          prompt: "/code-review:code-review ${{ github.repository }}/pull/${{ github.event.pull_request.number }} --comment"
          claude_args: '--allowedTools "Bash(gh api*),Bash(gh pr*),Bash(git*),Bash(linear*)"'

[schpet]

is this already supported? https://github.com/schpet/linear-cli/blob/main/docs/authentication.md#environment-variable

[schpet]

my assumption is that this already works how you describe but let me know if it's not working (i.e. a regression) and i can fix it