Meet Pipeline Editor, your one-stop shop for building a CI/CD pipeline

Introduced the Pipeline Editor, a dedicated interface for authoring `.gitlab-ci.yml` files. Key features include continuous validation of pipeline configurations, a pipeline visualizer that shows the pipeline structure before execution, an expanded view that merges `include` and `extends` directives for better readability of complex configurations, and an integrated CI linter that provides detailed job information. This aims to simplify CI/CD pipeline authoring and reduce errors.