feat: add CI agent for fixing CI failures

[mathislucka]

This PR adds a new agent pipeline for automatically fixing CI failures. The CI agent works in a similar way to the GitHub agent but is triggered by CI failures rather than GitHub issues.

Changes Made

1. Created new CI-specific components:

   • CIOutputParser: Parses CI output logs into Haystack documents
   • CIBranchCreator: Creates a new branch for fixing CI issues
   • CIDocumentToChatMessageConverter: Converts CI failures into structured chat messages

2. Implemented a CI agent pipeline:

   • Added ci_agent.py pipeline similar to the GitHub agent but adapted for CI input
   • Created a system prompt specifically for fixing CI issues
   • Registered the pipeline so it's available for deployment

3. Added a GitHub workflow:

   • Created ai_ci_processor.yaml workflow that runs on CI failure
   • The workflow downloads CI logs and sends them to the deepset Cloud pipeline
   • CI agent then analyzes failures and creates a PR with fixes

Implementation Details

The CI agent has the same core functionality as the GitHub agent but uses different input sources and parsing mechanisms:

1. The agent receives CI log output as input (via the query parameter)
2. It parses logs to identify test failures, linting errors, and other issues
3. It creates a new branch with timestamp-based naming (e.g., fix-ci-1234567890)
4. It makes the necessary code changes to fix the issues
5. It creates a pull request with the fixes

Testing Considerations

To test this implementation:

• Manually trigger the pipeline with sample CI logs to verify parsing
• Verify branch creation works with the timestamp-based naming
• Check that the agent correctly identifies and fixes common CI issues
• Ensure PRs are created with proper title and description

Next Steps

• Monitor usage and refine the CI log parsing to better identify different types of failures
• Consider adding CI-specific tooling like test runners or linting checks the agent could use
• Enhance the system prompt with more detailed instructions for specific types of CI failures

Closes #17