refactor: centralize section config — remove all hardcoded section lists

- New packages/config/src/sections.ts: SECTIONS, SECTIONS_BY_ID, SECTION_IDS
  (no Node.js built-in imports — safe for client components)
- New package entrypoint: @mcpedia/config/sections (exports only sections.ts)
- Client components import from @mcpedia/config/sections (no node:fs in bundle)
- Server components import from @mcpedia/config (has env/fs, server-only)
- Removed hardcoded SECTIONS/SECTION_LABEL/SECTION_ICON from:
  - [section]/page.tsx (was inline array)
  - [section]/[...slug]/page.tsx (was hardcoded Record maps)
  - Sidebar.tsx (was inline array)
  - layout.tsx (was inline array)
  - page.tsx (was inline array)
  - create/page.tsx (was inline array via SECTIONS import)
- Added @mcpedia/config/sections entrypoint to package.json exports

apps/web/app/create/page.tsx

@@ -1,33 +1,31 @@
 import { listDocuments, extractFoldersForSection } from "@mcpedia/core";
+import { SECTIONS } from "@mcpedia/config/sections";
+import { WEBHOOK_SECRET } from "@mcpedia/config";
 import { cookies } from "next/headers";
 import { redirect } from "next/navigation";
 import DocForm from "@/components/DocForm";
-import { WEBHOOK_SECRET } from "@mcpedia/config";
-
-export const dynamic = "force-dynamic";
 
 export default async function CreatePage() {
   const cookieStore = await cookies();
-  const canEdit = cookieStore.get("mcpedia_admin")?.value != null;
-  if (!canEdit) redirect("/login");
+  const isAdmin = cookieStore.get("mcpedia_admin")?.value != null;
+  if (!isAdmin) redirect("/login");
 
-  const allDocs = await listDocuments();
-  const docPaths = allDocs.map((d) => d.path);
-
-  // Build folder suggestions per section using the shared core helper
-  const sections = ["docs", "writeups", "research", "notes"];
-  const foldersBySection: Record<string, string[]> = {};
-  for (const sec of sections) {
-    foldersBySection[sec] = extractFoldersForSection(docPaths, sec);
-  }
+  const all = await listDocuments();
+  const docPaths = all.map((d) => d.path);
 
   return (
     <div>
-      <h1 className="text-3xl font-medium text-[#f7f8f8] mb-6">Create Document</h1>
+      <div className="flex items-center gap-2 mb-6">
+        <span className="text-2xl">✏️</span>
+        <h1 className="text-2xl font-medium text-[#f7f8f8]">Create Document</h1>
+      </div>
+
       <DocForm
         mode="create"
         secret={WEBHOOK_SECRET}
-        existingFolders={foldersBySection}
+        existingFolders={Object.fromEntries(
+          SECTIONS.map((s) => [s.id, extractFoldersForSection(docPaths, s.id)])
+        )}
       />
     </div>
   );