feat: Phase 14 — hierarchical folder structure (GitHub-style nested folders)

- Section index pages ([section]/page.tsx): shows folder tree + flat doc list
- Folder index pages: [section]/[...slug]/page.tsx detects folder paths
  and renders subfolder + document listing instead of 404
- Sidebar tree: hierarchical grouping from flat doc slugs, folder icons (📁)
  with proper indentation per depth level
- DocForm v2: parent folder dropdown (populated from existing folders),
  slug input for leaf name, resolved path display
- Core helpers: extractFoldersForSection + classifyPath exported from @mcpedia/core
- CTF writeup reorganized: pwn-100 ret2win moved into pwn/ subfolder
- _index.md folder intro pages for ctf/ and defcon-quals-2024/
- STANDARD_KEYS includes extraFields to avoid badge duplication

apps/web/app/create/page.tsx

@@ -1,44 +1,34 @@
-import { WEBHOOK_SECRET } from "@mcpedia/config";
+import { listDocuments, extractFoldersForSection } from "@mcpedia/core";
 import { cookies } from "next/headers";
+import { redirect } from "next/navigation";
 import DocForm from "@/components/DocForm";
-import Link from "next/link";
+import { WEBHOOK_SECRET } from "@mcpedia/config";
+
+export const dynamic = "force-dynamic";
 
-// GET /create — show the document create form.
-// Requires admin cookie auth.
 export default async function CreatePage() {
   const cookieStore = await cookies();
   const canEdit = cookieStore.get("mcpedia_admin")?.value != null;
-  if (!canEdit) {
-    return (
-      <div className="text-center py-16">
-        <h1 className="text-2xl font-light text-[#f7f8f8] mb-4">
-          Authentication required
-        </h1>
-        <p className="text-[#8a8f98] mb-6">
-          You must be logged in to create documents.
-        </p>
-        <Link
-          href="/login"
-          className="inline-flex items-center gap-2 px-4 py-2 rounded bg-[#5e6ad2] text-white hover:bg-[#7170ff] transition-colors font-medium text-sm"
-        >
-          Login
-        </Link>
-      </div>
-    );
+  if (!canEdit) redirect("/login");
+
+  const allDocs = await listDocuments();
+
+  // Build folder suggestions per section using the shared helper from core
+  const sections = ["docs", "writeups", "research", "notes"];
+  const docPaths = allDocs.map((d) => d.path);
+  const foldersBySection: Record<string, string[]> = {};
+  for (const sec of sections) {
+    foldersBySection[sec] = extractFoldersForSection(docPaths, sec);
   }
 
   return (
     <div>
-      <Link
-        href="/"
-        className="text-xs text-[#8a8f98] hover:text-[#d0d6e0] mb-4 inline-block"
-      >
-        ← Back
-      </Link>
-      <h1 className="text-2xl font-light text-[#f7f8f8] mb-6">
-        Create Document
-      </h1>
-      <DocForm mode="create" secret={WEBHOOK_SECRET} />
+      <h1 className="text-3xl font-medium text-[#f7f8f8] mb-6">Create Document</h1>
+      <DocForm
+        mode="create"
+        secret={WEBHOOK_SECRET}
+        existingFolders={foldersBySection}
+      />
     </div>
   );
 }