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>

website/.astro/collections/docs.schema.json

@@ -0,0 +1,33 @@
+{
+  "$ref": "#/definitions/docs",
+  "definitions": {
+    "docs": {
+      "type": "object",
+      "properties": {
+        "title": {
+          "type": "string"
+        },
+        "description": {
+          "type": "string"
+        },
+        "section": {
+          "type": "string"
+        },
+        "order": {
+          "type": "number"
+        },
+        "$schema": {
+          "type": "string"
+        }
+      },
+      "required": [
+        "title",
+        "description",
+        "section",
+        "order"
+      ],
+      "additionalProperties": false
+    }
+  },
+  "$schema": "http://json-schema.org/draft-07/schema#"
+}