Deduplicate entry points and templates

CLAUDE.md and AGENTS.md (now a symlink) shrink to a pointer at the
bootstrap, which absorbs the rule-editing instructions. The two
identical per-tool templates merge into rules/ai/AGENT.template.md.
README drops the read path duplicated from the bootstrap. The
web-visual-baseline starter CSS/HTML duplicated assets/view.css and is
removed in favor of the vendored assets.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

rules/patterns/web-visual-baseline/contract.md

@@ -14,7 +14,7 @@ in this pattern:
 - `assets/upload.html`
 
 When a project does not already have an established design system, use this baseline by default.
-Copyable starter CSS and HTML live in `README.md` next to this contract.
+Copy `assets/view.css` as the starting stylesheet and adapt tokens; do not rewrite it from prose.
 
 ## Core Direction