Simplify README; move detailed content into docs/

[surrealwolf]

Goal

Simplify the repository README so it stays a short, scannable entry point, and move deeper material into a docs/ folder.

Keep in the README

• One-line purpose / what this repo is
• Hero/banner graphic (if present)
• Quick start (minimal commands to get running)
• Links to detailed docs
• License / status badges (optional, keep light)

Move into docs/

• Architecture deep-dives
• Runbooks / operations
• Detailed configuration matrices
• Long prerequisite lists and troubleshooting
• Design notes, ADRs, and historical context

Suggested structure (adapt as needed):

docs/
  README.md          # docs index
  ARCHITECTURE.md
  QUICKSTART.md      # only if README would otherwise grow
  ...
  assets/            # README hero + other images

Org alignment (light touch)

DataKnifeAI focuses on learning and solving problems with AI tools in ways that stay maintainable, automated, and stable, preferring freedom-respecting open software when it fits. The README should reflect that calmly—no org-logo reuse as the repo graphic; each project keeps its own visual identity.

Out of scope for this issue

• Full rewrite of all docs in one PR (incremental is fine)
• Replacing upstream fork branding wholesale without a clear fork strategy

Acceptance criteria

• README is short enough to read in ~1–2 screens
• Non-essential detail lives under docs/ with clear links from the README
• Hero graphic (if any) remains near the top without crowding the intro