feat: add reusable CTA assistant GitHub action

[bkrem]

Summary

• Converted existing CLA workflow to reusable composite action
• Updated all terminology from CLA to CTA (Copyright Transfer Agreement)
• Maintained full backward compatibility with all configuration options
• Added comprehensive documentation and usage examples

Key Features

• Reusable composite action - Can be used across multiple repositories
• Configurable CTA document URL - Point to your organization's CTA
• Flexible signature storage - Local or remote repository options
• Customizable messaging - All PR comments and commit messages configurable
• Full permission control - Explicit permission requirements documented

Implementation Details

This action is a wrapper around the upstream contributor-assistant/github-action that provides:

• Simplified configuration for WalletConnect repositories
• CTA-specific terminology and defaults
• Reusable composite action structure
• Comprehensive documentation and examples

Usage Example

name: "CTA Assistant"
on:
  issue_comment:
    types: [created]
  pull_request_target:
    types: [opened, closed, synchronize]

permissions:
  actions: write
  contents: write
  pull-requests: write
  statuses: write

jobs:
  CTA:
    runs-on: ubuntu-latest
    steps:
      - uses: walletconnect/actions/github/cta-assistant@v1
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Test plan

• Test basic CTA workflow with default settings
• Test custom CTA document URL configuration
• Test remote signature storage functionality
• Verify all permission requirements work correctly
• Test contributor signing flow end-to-end

TODOs

• Replace the stopgap gist I used here with a proper public version of the CTA
• Delete the stopgap gist
• Set up known allowlist (including bots)
• Test this composite action on a real repo: https://github.com/reown-com/cloudflare-exporter/pull/32
• Test bot workflow (via Devin PR): https://github.com/reown-com/cloudflare-exporter/pull/41

[Copilot]

Pull Request Overview

This PR introduces a reusable GitHub Action for managing Copyright Transfer Agreement (CTA) signatures from contributors. The action is built as a composite action that wraps the existing contributor-assistant/github-action and provides a standardized interface for CTA workflows across repositories.

Key changes:

• Created a composite action configuration file with comprehensive input parameters for CTA customization
• Added detailed documentation with usage examples, configuration options, and troubleshooting guidance
• Implemented flexible signature storage options supporting both local and remote repository configurations

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
github/cta-assistant/action.yml	Defines the composite action with inputs for CTA document URL, signature storage, commit messages, and remote storage options
github/cta-assistant/README.md	Comprehensive documentation covering setup, configuration, permissions, and troubleshooting for the CTA assistant action

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