Add public help center with 10 topic pages and improve contractor/residence cards

- Create complete help center at /help with getting-started, residences, tasks,
  contractors, documents, sharing, dashboard, notifications, subscription, and
  account pages
- Add shared help components: sidebar, header, footer, article/section wrappers,
  screenshot placeholders, and tip/note/warning callouts
- Add /help to middleware public paths so it loads without auth
- Add Help Center link to landing page footer
- Link contractor import dialog to /help/sharing
- Make contractor cards fully clickable with consistent height
- Add clear button to contractor specialty filter
- Fix residence card height consistency in grid

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/help/layout.tsx

@@ -0,0 +1,29 @@
+import type { Metadata } from "next";
+import { HelpHeader } from "@/components/help/help-header";
+import { HelpSidebar } from "@/components/help/help-sidebar";
+import { HelpFooter } from "@/components/help/help-footer";
+
+export const metadata: Metadata = {
+  title: "Help Center",
+  description:
+    "Learn how to use honeyDue to manage your home maintenance, tasks, contractors, and documents.",
+};
+
+export default function HelpLayout({ children }: { children: React.ReactNode }) {
+  return (
+    <div className="min-h-screen bg-[#FAFAF7] text-[#2D3436] font-sans selection:bg-[#6B8F71]/20 flex flex-col">
+      <HelpHeader />
+      <div className="flex-1 max-w-7xl mx-auto w-full px-6 py-10">
+        <div className="flex gap-10">
+          <aside className="hidden lg:block w-56 shrink-0">
+            <div className="sticky top-24">
+              <HelpSidebar />
+            </div>
+          </aside>
+          <main className="flex-1 min-w-0">{children}</main>
+        </div>
+      </div>
+      <HelpFooter />
+    </div>
+  );
+}