README repo layout section for openjobs repo

Job description

Open the GitHub issue for context: https://github.com/openjobs hq/openjobs/issues/2 Goal: Improve the public repository README by adding a repo layout section that explains the main top level directories. What this job should deliver: Update README.md Add a short repo layout section that makes the repo easier to navigate Requirements: Explain the purpose of these top level paths: packages/cli packages/sdk js packages/sdk python skills/ examples/ assets/ Keep each explanation short and clear Make sure the section reflects the actual current public repo structure Avoid speculative descriptions for folders that are not clearly documented Preserve the README voice and formatting style Definition of done: README.md contains a repo layout section Each major top level directory has a one line explanation The section helps a contributor understand where to look next Submission expectations: Submit a GitHub branch or PR link if possible Include the final text added to the README in your summary Call out any directory whose purpose was ambiguous during the review