§22 S2: collection directory at /p/<project>/ (1 → redirect, 2+ → list)

Replace DefaultCollectionRedirect with a CollectionDirectory that lists the
project's visible collections, or redirects into the sole one when there is
exactly one (preserving the S1 C3.7/C3.8 single-collection UX). The
create-first-collection empty state is S4.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/App.jsx

@@ -15,6 +15,7 @@ import RFCView from './components/RFCView.jsx'
 import PRView from './components/PRView.jsx'
 import ProposalView from './components/ProposalView.jsx'
 import ProposeModal from './components/ProposeModal.jsx'
+import CollectionDirectory from './components/CollectionDirectory.jsx'
 import ContributeRequestForm from './components/ContributeRequestForm.jsx'
 import Landing from './components/Landing.jsx'
 import Login from './components/Login.jsx'
@@ -364,9 +365,10 @@ export default function App() {
               />
               <main className="main-pane">
                 <Routes>
-                  {/* §22 three-tier (C3.7): the project landing redirects into
-                      its sole/default collection (S1: the `default` one). */}
-                  <Route path="" element={<DefaultCollectionRedirect />} />
+                  {/* §22 S2: the project landing is the collection directory —
+                      it lists collections, or (C3.7/C3.8) redirects into the
+                      sole visible collection when there is exactly one. */}
+                  <Route path="" element={<CollectionDirectoryRoute />} />
                   {/* Backcompat: the shipped v0.35.0 corpus URLs without a
                       /c/<collection>/ segment redirect into the default
                       collection, so old bookmarks keep working. */}
@@ -419,12 +421,12 @@ export default function App() {
   )
 }
 
-// §22 three-tier — corpus redirects mounted under /p/:projectId/*.
-// C3.7: the project landing skips the (single-collection) directory and lands in
-// the project's default collection.
-function DefaultCollectionRedirect() {
+// §22 S2 — the project landing at /p/:projectId/ is the collection directory.
+// A tiny wrapper reads the route's projectId and hands it to CollectionDirectory
+// (which lists collections, or redirects into the sole one — C3.7/C3.8).
+function CollectionDirectoryRoute() {
   const { projectId } = useParams()
-  return <Navigate to={`/p/${projectId}/c/${DEFAULT_COLLECTION}/`} replace />
+  return <CollectionDirectory projectId={projectId} />
 }
 
 // Backcompat for the shipped v0.35.0 corpus URLs that lacked the

frontend/src/components/CollectionDirectory.jsx

@@ -0,0 +1,51 @@
+// §22 S2 — the project collection directory at `/p/<project>/`. Lists the
+// project's caller-visible collections as cards linking into each collection's
+// `/p/<project>/c/<collection>/` home. When exactly one collection is visible
+// the directory is skipped and we redirect straight into it (the S1 C3.7/C3.8
+// single-collection UX, preserved). The role-keyed "Create your first
+// collection" empty state is S4; S2 shows a minimal note when there are none.
+import { useEffect, useState } from 'react'
+import { Link, Navigate } from 'react-router-dom'
+import { listCollections } from '../api'
+import { collectionHome } from '../lib/entryPaths'
+import { entryNoun } from './ProjectLayout.jsx'
+
+export default function CollectionDirectory({ projectId }) {
+  const [cols, setCols] = useState(null)
+  useEffect(() => {
+    let live = true
+    listCollections(projectId)
+      .then(d => { if (live) setCols(d.items) })
+      .catch(() => { if (live) setCols([]) })
+    return () => { live = false }
+  }, [projectId])
+
+  if (cols === null) {
+    return <main className="chrome-pane"><div className="boot">Loading…</div></main>
+  }
+  // C3.7/C3.8: a single visible collection skips the directory.
+  if (cols.length === 1) {
+    return <Navigate to={collectionHome(projectId, cols[0].id)} replace />
+  }
+  return (
+    <main className="chrome-pane">
+      <div className="directory">
+        <h1>Collections</h1>
+        {cols.length === 0 ? (
+          <p className="directory-tagline">No collections yet.</p>
+        ) : (
+          <ul className="directory-list">
+            {cols.map(c => (
+              <li key={c.id} className="directory-card">
+                <Link to={collectionHome(projectId, c.id)}>
+                  <span className="directory-card-name">{c.name || c.id}</span>
+                  <span className="directory-card-type">{entryNoun(c.type)}s</span>
+                </Link>
+              </li>
+            ))}
+          </ul>
+        )}
+      </div>
+    </main>
+  )
+}

frontend/src/components/CollectionDirectory.test.jsx

@@ -0,0 +1,48 @@
+import React from 'react'
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, waitFor } from '@testing-library/react'
+import { MemoryRouter, Routes, Route } from 'react-router-dom'
+
+let mockItems = []
+vi.mock('../api', () => ({
+  listCollections: vi.fn(async () => ({ items: mockItems })),
+}))
+import CollectionDirectory from './CollectionDirectory.jsx'
+
+beforeEach(() => { mockItems = [] })
+
+function renderDir(items) {
+  mockItems = items
+  return render(
+    <MemoryRouter initialEntries={["/p/ohm/"]}>
+      <Routes>
+        <Route path="/p/:projectId/*" element={<CollectionDirectory projectId="ohm" />} />
+        <Route path="/p/:projectId/c/:collectionId/*" element={<div>collection home</div>} />
+      </Routes>
+    </MemoryRouter>,
+  )
+}
+
+describe('CollectionDirectory', () => {
+  it('lists a card per collection with the type-driven noun + link when 2+', async () => {
+    renderDir([
+      { id: 'default', name: 'Model', type: 'document' },
+      { id: 'features', name: 'Scenarios', type: 'bdd' },
+    ])
+    await waitFor(() => expect(screen.getByText('Scenarios')).toBeInTheDocument())
+    expect(screen.getByText('Model').closest('a')).toHaveAttribute('href', '/p/ohm/c/default/')
+    expect(screen.getByText('Scenarios').closest('a')).toHaveAttribute('href', '/p/ohm/c/features/')
+    expect(screen.getByText('RFCs')).toBeInTheDocument()       // document → RFCs
+    expect(screen.getByText('Features')).toBeInTheDocument()   // bdd → Features (type noun)
+  })
+
+  it('redirects into the sole collection when exactly one is visible', async () => {
+    renderDir([{ id: 'default', name: 'Model', type: 'document' }])
+    await waitFor(() => expect(screen.getByText('collection home')).toBeInTheDocument())
+  })
+
+  it('shows a minimal empty note when there are no collections', async () => {
+    renderDir([])
+    await waitFor(() => expect(screen.getByText('No collections yet.')).toBeInTheDocument())
+  })
+})