chore: mark completion of sessions and SWOT components in devbook.md; add @hello-pangea/dnd dependency for drag & drop functionality

src/app/sessions/[id]/page.tsx

@@ -0,0 +1,68 @@
+import { notFound } from 'next/navigation';
+import Link from 'next/link';
+import { auth } from '@/lib/auth';
+import { getSessionById } from '@/services/sessions';
+import { SwotBoard } from '@/components/swot/SwotBoard';
+import { Badge } from '@/components/ui';
+
+interface SessionPageProps {
+  params: Promise<{ id: string }>;
+}
+
+export default async function SessionPage({ params }: SessionPageProps) {
+  const { id } = await params;
+  const authSession = await auth();
+
+  if (!authSession?.user?.id) {
+    return null;
+  }
+
+  const session = await getSessionById(id, authSession.user.id);
+
+  if (!session) {
+    notFound();
+  }
+
+  return (
+    <main className="mx-auto max-w-7xl px-4 py-8">
+      {/* Header */}
+      <div className="mb-8">
+        <div className="flex items-center gap-2 text-sm text-muted mb-2">
+          <Link href="/sessions" className="hover:text-foreground">
+            Mes Sessions
+          </Link>
+          <span>/</span>
+          <span className="text-foreground">{session.title}</span>
+        </div>
+
+        <div className="flex items-start justify-between">
+          <div>
+            <h1 className="text-3xl font-bold text-foreground">{session.title}</h1>
+            <p className="mt-1 text-lg text-muted">
+              👤 {session.collaborator}
+            </p>
+          </div>
+          <div className="flex items-center gap-3">
+            <Badge variant="primary">{session.items.length} items</Badge>
+            <Badge variant="success">{session.actions.length} actions</Badge>
+            <span className="text-sm text-muted">
+              {new Date(session.date).toLocaleDateString('fr-FR', {
+                day: 'numeric',
+                month: 'long',
+                year: 'numeric',
+              })}
+            </span>
+          </div>
+        </div>
+      </div>
+
+      {/* SWOT Board */}
+      <SwotBoard
+        sessionId={session.id}
+        items={session.items}
+        actions={session.actions}
+      />
+    </main>
+  );
+}
+