Allow to trigger code review on another repo

For easily testing code review, allow to run the action manually.

The target repo and PR can be specified, as well as the plugin
marketplace to install.

Issue: ZENKO-5260

Author: francoisferrand

.github/workflows/claude-code-review.yml

@@ -31,6 +31,14 @@ on:
           - comment: post as a PR comment
           - auto: check if allowed, otherwise post as a comment
         default: auto
+      repository:
+        type: string
+        description: Name of the repository to review (without owner — must be in the same owner as the workflow). Defaults to the current repository.
+        default: ${{ github.event.repository.name }}
+      pull_request_number:
+        type: string
+        description: Pull request number to review. Defaults to the PR that triggered the workflow.
+        default: ${{ github.event.pull_request.number }}
       ACTIONS_APP_ID:
         type: string
         description: >
@@ -68,8 +76,32 @@ jobs:
       id-token: write  # claude-code-action needs this to authenticate with GitHub
 
     steps:
+      - name: Get token for PR repository
+        if: inputs.repository
+        id: pr-token
+        uses: actions/create-github-app-token@v3
+        with:
+          app-id: ${{ inputs.ACTIONS_APP_ID }}
+          private-key: ${{ secrets.ACTIONS_APP_PRIVATE_KEY }}
+          owner: ${{ github.repository_owner }}
+          repositories: ${{ inputs.repository }}
+
+      - name: Compute PR branch
+        if: inputs.repository || inputs.pull_request_number
+        id: pr-branch
+        env:
+          GH_TOKEN: ${{ steps.pr-token.outputs.token || github.token }}
+          REPOSITORY: ${{ github.repository_owner }}/${{ inputs.repository }}
+          PR_NUMBER: ${{ inputs.pull_request_number }}
+        run: |
+          branch=$(gh pr view "$PR_NUMBER" --repo "$REPOSITORY" --json headRefName --jq .headRefName)
+          echo "ref=$branch" >> "$GITHUB_OUTPUT"
+
       - uses: actions/checkout@v6
         with:
+          repository: ${{ github.repository_owner }}/${{ inputs.repository }}
+          ref: ${{ steps.pr-branch.outputs.ref || github.ref }}
+          token: ${{ steps.pr-token.outputs.token || github.token }}
           fetch-depth: 1
 
       - name: Identify marketplaces needing local checkout
@@ -135,7 +167,8 @@ jobs:
         uses: anthropics/claude-code-action@v1
         with:
           use_vertex: "true"
-          prompt: "/review-pr REPO: ${{ github.repository }} PR_NUMBER: ${{ github.event.pull_request.number }}"
+          github_token: ${{ steps.pr-token.outputs.token || github.token }}
+          prompt: "/review-pr REPO: ${{ github.repository_owner }}/${{ inputs.repository }} PR_NUMBER: ${{ inputs.pull_request_number }}"
           claude_args: |
             --allowedTools "Read" "Bash(git diff *)" "Bash(git log *)" "Bash(git show *)" "Bash(gh repo view *)" "Bash(gh pr view *)" "Bash(gh pr diff *)" "Bash(gh pr checks *)" "Bash(gh pr comment *)" "Bash(gh api *repos/*/pulls/*/comments*)" "Bash(gh api *issues/*/comments*)" "Bash(gh api *repos/*/check-runs*)"
             --model "${{ inputs.model }}"