refactor: Phase 14 consistency pass — remove duplicate, fix breadcrumbs, header nav, DocForm

- Delete apps/web/app/docs/page.tsx (superseded by generic [section]/page.tsx)
- Homepage: inline folder tree per section card (📁📄), removed Suspense
- Doc page breadcrumbs: dynamic path from doc.slug (was hardcoded 'Docs')
- Header nav: added Writeups/Research/Notes section links
- DocForm: parent folder dropdown populated from existing folders, slug read-
  only in edit mode, edit mode keeps section disabled, resolved slug shown
- create/page.tsx: use extractFoldersForSection from @mcpedia/core (dedup)
- Removed unused extractFoldersForSection import from page.tsx

apps/web/app/create/page.tsx

@@ -12,10 +12,10 @@ export default async function CreatePage() {
   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);
+
+  // 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);