Rename .pi to .feynman, rename citation agent to verifier, add website, skills, and docs

- Rename project config dir from .pi/ to .feynman/ (Pi supports this via piConfig.configDir)
- Rename citation agent to verifier across all prompts, agents, skills, and docs
- Add website with homepage and 24 doc pages (Astro + Tailwind)
- Add skills for all workflows (deep-research, lit, review, audit, replicate, compare, draft, autoresearch, watch, jobs, session-log, agentcomputer)
- Add Pi-native prompt frontmatter (args, section, topLevelCli) and read at runtime
- Remove sync-docs generation layer — docs are standalone
- Remove metadata/prompts.mjs and metadata/packages.mjs — not needed at runtime
- Rewrite README and homepage copy
- Add environment selection to /replicate before executing
- Add prompts/delegate.md and AGENTS.md

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

prompts/draft.md

@@ -1,10 +1,13 @@
 ---
 description: Turn research findings into a polished paper-style draft with equations, sections, and explicit claims.
+args: <topic>
+section: Research Workflows
+topLevelCli: true
 ---
 Write a paper-style draft for: $@
 
 Requirements:
-- Use the `writer` subagent when the draft should be produced from already-collected notes, then use the `citation` subagent to add inline citations and verify sources.
+- Use the `writer` subagent when the draft should be produced from already-collected notes, then use the `verifier` subagent to add inline citations and verify sources.
 - Include at minimum: title, abstract, problem statement, related work, method or synthesis, evidence or experiments, limitations, conclusion.
 - Use clean Markdown with LaTeX where equations materially help.
 - Save exactly one draft to `papers/` as markdown.