feat(m7): markdown notes with CRUD, preview, search, tests, e2e

- ProjectNoteRepository (CRUD, soft-delete, search title/body/tags,
  pinned-first ordering, index usage) + NoteService (membership permission,
  author/admin edit/delete, note_updated notification to other members,
  note_created/note_updated activity logs, pin/tags)
- APIs: notes list/create/detail/edit/delete
- Screens: notes list + NoteForm, note detail + NoteEditor + MarkdownBody
  preview, ProjectNav メモ link
- Unit tests (ProjectNoteRepository, NoteService) + e2e markdown-notes.spec

app/projects/[projectId]/notes/[noteId]/page.tsx

@@ -0,0 +1,63 @@
+import { redirect } from 'next/navigation';
+import { getCurrentUser, toPublicUser } from '@/lib/auth/getCurrentUser';
+import { createNoteService } from '@/lib/api/services';
+import { Header } from '@/components/layout/Header';
+import { ProjectNav } from '@/components/layout/ProjectNav';
+import { MarkdownBody } from '@/components/board/MarkdownBody';
+import { NoteEditor } from '@/components/notes/NoteEditor';
+import { ForbiddenError, NotFoundError } from '@/lib/errors';
+import type { ProjectNote } from '@/lib/types';
+
+export const dynamic = 'force-dynamic';
+
+export default async function NoteDetailPage({
+  params,
+}: {
+  params: Promise<{ projectId: string; noteId: string }>;
+}) {
+  const user = await getCurrentUser();
+  if (!user) redirect('/login');
+  const { projectId, noteId } = await params;
+
+  const noteService = createNoteService();
+  let note: ProjectNote;
+  try {
+    note = noteService.getNote(user.id, Number(noteId));
+  } catch (error) {
+    if (error instanceof ForbiddenError || error instanceof NotFoundError) {
+      redirect(`/projects/${projectId}/notes`);
+    }
+    throw error;
+  }
+
+  return (
+    <div className="min-h-screen bg-gray-50">
+      <Header user={toPublicUser(user)} />
+      <ProjectNav projectId={Number(projectId)} active="notes" />
+      <main className="mx-auto max-w-3xl space-y-6 p-6">
+        <a
+          href={`/projects/${projectId}/notes`}
+          className="text-sm text-blue-600 hover:underline"
+        >
+          ← メモ一覧へ
+        </a>
+        <div className="rounded-lg border bg-white p-6 shadow-sm">
+          <h1 className="text-2xl font-bold">
+            {note.isPinned === 1 && '📌 '}
+            {note.title}
+          </h1>
+          {note.tags && (
+            <p className="mt-1 text-xs text-gray-500">{note.tags}</p>
+          )}
+          <div className="mt-4">
+            <MarkdownBody bodyMd={note.bodyMd} />
+          </div>
+          <p className="mt-4 text-xs text-gray-400">
+            作成: {note.createdAt} / 更新: {note.updatedAt}
+          </p>
+        </div>
+        <NoteEditor projectId={Number(projectId)} note={note} />
+      </main>
+    </div>
+  );
+}

app/projects/[projectId]/notes/page.tsx

@@ -0,0 +1,74 @@
+import { redirect } from 'next/navigation';
+import { getCurrentUser, toPublicUser } from '@/lib/auth/getCurrentUser';
+import { createNoteService, createProjectService } from '@/lib/api/services';
+import { Header } from '@/components/layout/Header';
+import { ProjectNav } from '@/components/layout/ProjectNav';
+import { NoteForm } from '@/components/notes/NoteForm';
+import { ForbiddenError, NotFoundError } from '@/lib/errors';
+
+export const dynamic = 'force-dynamic';
+
+export default async function NotesPage({
+  params,
+  searchParams,
+}: {
+  params: Promise<{ projectId: string }>;
+  searchParams: Promise<{ q?: string; page?: string }>;
+}) {
+  const user = await getCurrentUser();
+  if (!user) redirect('/login');
+  const { projectId } = await params;
+  const { q, page } = await searchParams;
+
+  const projectService = createProjectService();
+  let project: Awaited<ReturnType<typeof projectService.getProject>>;
+  try {
+    project = projectService.getProject(user.id, Number(projectId));
+  } catch (error) {
+    if (error instanceof ForbiddenError || error instanceof NotFoundError) {
+      redirect('/dashboard');
+    }
+    throw error;
+  }
+
+  const noteService = createNoteService();
+  const { items } = noteService.listNotes(user.id, project.id, {
+    page: Number(page ?? '1') || 1,
+    search: q,
+  });
+
+  return (
+    <div className="min-h-screen bg-gray-50">
+      <Header user={toPublicUser(user)} />
+      <ProjectNav projectId={project.id} active="notes" />
+      <main className="mx-auto max-w-3xl space-y-6 p-6">
+        <h1 className="text-2xl font-bold">Markdownメモ</h1>
+        <NoteForm projectId={project.id} />
+        <section className="space-y-3">
+          {items.length === 0 ? (
+            <p className="text-sm text-gray-400">メモはありません。</p>
+          ) : (
+            items.map((note) => (
+              <a
+                key={note.id}
+                href={`/projects/${project.id}/notes/${note.id}`}
+                className="block rounded-lg border bg-white p-4 shadow-sm hover:shadow-md"
+              >
+                <div className="flex items-center justify-between">
+                  <h3 className="font-semibold text-gray-800">
+                    {note.isPinned === 1 && '📌 '}
+                    {note.title}
+                  </h3>
+                  {note.tags && (
+                    <span className="text-xs text-gray-500">{note.tags}</span>
+                  )}
+                </div>
+                <p className="mt-1 text-xs text-gray-400">{note.updatedAt}</p>
+              </a>
+            ))
+          )}
+        </section>
+      </main>
+    </div>
+  );
+}