Initialize Ralph

Run ralph-init to scaffold the Ralph autonomous agent structure.

ralph-init

This creates:

• ralph/ directory with loop script and prompt files
• ralph/prd.json story queue
• ralph/progress.txt progress log
• ralph/RALPH_PROMPT.md prompt template
• ralph/scripts/ with CI, status, update, and stream filtering utilities
• .ralph/ output directory (gitignored) during runs

After running, tell the user to:

1. Edit ralph/prd.json
2. Edit ralph/scripts/ci-check.sh
3. Optionally customize ralph/RALPH_PROMPT.md
4. Run ./ralph/scripts/prd-status.sh
5. Run ./ralph/ralph.sh