Multi-framework template support

[adamdaum]

Summary

Currently, create-ralph-loop only scaffolds Next.js projects (App Router + TypeScript + Tailwind + shadcn/ui). Many teams use different stacks, and the loop workflow itself is framework-agnostic.

Proposal

Add support for additional framework templates, starting with the most popular options:

• Python: Django, FastAPI, Flask
• Ruby: Rails
• JavaScript/TypeScript: Express, Remix, Astro, SvelteKit

Implementation Ideas

• Introduce a --template or --framework CLI flag (e.g., npx create-ralph-loop my-app --template fastapi)
• Move the current Next.js template into templates/nextjs/
• Abstract shared files (AGENTS.md, ralph.sh, prompts) from framework-specific files (init.sh, dev-up.sh, etc.)
• Each template provides its own init.sh, dev-up.sh/dev-down.sh, and default feature_list entries
• Update init_prompt.md and coding_prompt.md to be framework-aware (or use per-template prompt overrides)

Considerations

• The prompts reference Next.js-specific patterns (App Router, Prisma, shadcn). These need to be generalized or swapped per template.
• Dev server readiness detection (curl localhost:3000) needs to be configurable per framework.
• Testing tools differ (Jest/Playwright vs pytest/Selenium vs RSpec/Capybara).