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/replicate.md

@@ -1,12 +1,21 @@
 ---
 description: Plan or execute a replication workflow for a paper, claim, or benchmark.
+args: <paper>
+section: Research Workflows
+topLevelCli: true
 ---
 Design a replication plan for: $@
 
-Requirements:
-- Use the `researcher` subagent to extract implementation details from the target paper and any linked code.
-- Determine what code, datasets, metrics, and environment are needed.
-- If enough information is available locally, implement and run the replication steps.
-- Save notes, scripts, and results to disk in a reproducible layout.
-- Be explicit about what is verified, what is inferred, and what is still missing.
-- End with a `Sources` section containing paper and repository URLs.
+## Workflow
+
+1. **Extract** — Use the `researcher` subagent to pull implementation details from the target paper and any linked code.
+2. **Plan** — Determine what code, datasets, metrics, and environment are needed. Be explicit about what is verified, what is inferred, and what is still missing.
+3. **Environment** — Before running anything, ask the user where to execute:
+   - **Local** — run in the current working directory
+   - **Virtual environment** — create an isolated venv/conda env first
+   - **Cloud** — delegate to a remote Agent Computer machine via `/delegate`
+   - **Plan only** — produce the replication plan without executing
+4. **Execute** — If the user chose an execution environment, implement and run the replication steps there. Save notes, scripts, and results to disk in a reproducible layout.
+5. **Report** — End with a `Sources` section containing paper and repository URLs.
+
+Do not install packages, run training, or execute experiments without confirming the execution environment first.