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>

metadata/commands.d.mts

@@ -0,0 +1,46 @@
+export type PromptSpec = {
+	name: string;
+	description: string;
+	args: string;
+	section: string;
+	topLevelCli: boolean;
+};
+
+export type ExtensionCommandSpec = {
+	name: string;
+	args: string;
+	section: string;
+	description: string;
+	publicDocs: boolean;
+};
+
+export type LivePackageCommandSpec = {
+	name: string;
+	usage: string;
+};
+
+export type LivePackageCommandGroup = {
+	title: string;
+	commands: LivePackageCommandSpec[];
+};
+
+export type CliCommand = {
+	usage: string;
+	description: string;
+};
+
+export type CliCommandSection = {
+	title: string;
+	commands: CliCommand[];
+};
+
+export declare function readPromptSpecs(appRoot: string): PromptSpec[];
+export declare const extensionCommandSpecs: ExtensionCommandSpec[];
+export declare const livePackageCommandGroups: LivePackageCommandGroup[];
+export declare const cliCommandSections: CliCommandSection[];
+export declare const legacyFlags: CliCommand[];
+export declare const topLevelCommandNames: string[];
+
+export declare function formatSlashUsage(command: { name: string; args?: string }): string;
+export declare function formatCliWorkflowUsage(command: { name: string; args?: string }): string;
+export declare function getExtensionCommandSpec(name: string): ExtensionCommandSpec | undefined;