Gitignore docs/ (326 MB untracked JDK docs) to prevent accidental commits

[devops-thiago]

Background

The repository has a 326 MB docs/ directory (JDK 25 API/spec HTML docs used as the RAG corpus) that is entirely untracked and not listed in .gitignore. The workshop branch historically ignored docs/; main does not. A single git add -A would stage 326 MB of generated documentation.

Impact

• One careless command commits ~326 MB of JDK HTML docs, permanently bloating the repository and its history.
• Clone times and CI checkout times degrade for every contributor.
• Large files can hit GitHub's per-file size limits and cause push failures.

How to reproduce

1. From the repo root, run git add -A.
2. Observe docs/ being staged (~326 MB).

Where the fix should land

Add docs/ to .gitignore with a comment explaining it is the local JDK-docs corpus provisioned on the VM / mounted via Docker. Optionally commit docs/.gitkeep or docs/README.md documenting how to obtain the corpus, so the directory structure is documented without shipping the content.

Note: docker-compose.yml already mounts ./docs:/app/docs:ro — the ignore does not affect that volume mount.

Files touched

• .gitignore
• docs/.gitkeep or docs/README.md (optional)

Acceptance criteria

• git check-ignore docs/ reports the directory as ignored.
• git add -A no longer stages docs/.
• README or the new docs/README.md explains where the corpus comes from.