Code style guides

Each reference is one upstream guide converted to Markdown. Load only what the task needs:

1. Pick the reference for the language or framework below.
2. Read its index (the line range in the Index column). Each entry gives the line where a section starts.
3. Read only the sections you need, starting at those lines.

Code fences tagged good show recommended code; fences tagged bad show code to avoid. The project's own configuration, formatter, and surrounding code take precedence over these guides.